By Kenny Biddle

Terminology is important. The most basic element of useful discussion is that we are all “talking the same language” and agree on common definitions. Many paranormal groups use terminology incorrectly in articles, blogs and while “teaching” 101-type classes, in lectures or seminars, passing incorrect and sometimes outright false information to the public. Groups may also add their own spin (variations) to accepted definitions, in order to better fit their needs or belief. I’ve heard groups talk of “calibrated” devices, “puberty” causing paranormal phenomenon, and “finely tuned algorithms” that allow for paranormal-themed devices to detect and communicate with ghosts.In turn, this misinformation is passed along to others as they repeat the errors.

I have compiled this list of important words used in research and investigation. Terms include common logical fallacies, scientific, psychological and technical terms as well as photography-related terms that are commonly used. (See References section for all sources of the definitions.)

Please share this list with friends, team members, and other paranormal groups. It is not restricted to one aspect of the paranormal community, but all subject areas – ghosts, UFOs, Cryptozoology, psychics, etc.

Ad Hominem (Logical Fallacy) – An argument that attempts to counter another’s claim or conclusions by attacking the person, rather than addressing the argument itself. Calling someone a name is not in itself a logical fallacy, it is only a fallacy to claim that an argument is wrong because of a negative attribute of someone making the argument.

Ad Ignorantiam (Logical Fallacy) – States that a specific belief is true because we don’t know that it isn’t true. In order to make a positive claim, however, positive evidence for the specific claim must be presented. The absence of another explanation only means that we do not know – it doesn’t mean we get to make up a specific explanation.

Algorithm – A process or set of rules to be followed in calculations or other problem-solving operations, especially by a computer; a set of steps that are followed in order to solve a mathematical problem or to complete a computer process.

Altered States of Consciousness (ASCs) – A mental state other than ordinary waking consciousness, found during sleep, dreaming, psychoactive drug use, hypnosis, etc.

Amplitude – Height of a light or sound wave; pertaining to light, it refers to brightness, for sound, it refers to loudness.

Anecdotes – Short accounts of a particular incident, based on personal observation, case study reports, or random investigations rather than systematic scientific evaluation. Anecdotes are non-scientific observations which do not provide proof but may assist research efforts in guiding where to look deeper.

Anomalistic Psychology – The study of extraordinary phenomena of behavior and experience, including (but not restricted to) those which are often labeled “paranormal”. It is directed towards understanding bizarre experiences that many people have without assuming a priori that there is anything paranormal involved. It entails attempting to explain paranormal and related beliefs and ostensibly paranormal experiences in terms of known psychological and physical factors. Term was first suggested by the psychologists Leonard Zusne and Warren Jones in their book Anomalistic Psychology: A Study of Magical Thinking (1989) which systematically treats phenomena of human consciousness and behaviors that may appear to violate the laws of nature when they actually do not.

Anomaly – Something that deviates from what is standard, normal, or expected; an unexpected, unusual, or strange condition, situation, or quality.

Aperture – An opening inside the camera that allows the image sensor to catch a glimpse of the scene to capture. Aperture settings reflect the size of that hole. The larger the hole the more light that gets in – the smaller the hole the less light. Aperture is measured in ‘f-stops’ or f/number – for example f/2.8, f/4, f/5.6,f/8,f/22 etc. Moving from one f-stop to the next doubles or halves the size of the amount of opening in your lens (and the amount of light getting through).

Apophenia – The spontaneous perception of connections and meaningfulness of unrelated phenomena; the experience of seeing meaningful patterns or connections in random or meaningless data. The term was coined by neurologist Klaus Conrad and defined as the “unmotivated seeing of connections.” Pareidolia is a form of apophenia.

Appeal to Authority (Logical Fallacy) – A defense used in an argument that claims that because an authority thinks something, it must therefore be true. This fallacy is not meant to dismiss the claims of experts, or scientific consensus. It is not typically reasonable to disregard the claims of experts who have a demonstrated depth of knowledge unless one has a similar level of understanding and/or access to empirical evidence. However it is, entirely possible that the opinion of a person or institution of authority is wrong; therefore the authority that such a person or institution holds does not have any intrinsic bearing upon whether their claims are true or not.

Appeal to Emotion (Logical Fallacy) – An attempt to manipulate an emotional response in place of a valid or compelling argument. Appeals to emotion include appeals to fear, envy, hatred, pity, pride, and more.  A logically coherent argument may inspire emotion or have an emotional aspect, but the problem and fallacy occurs when emotion is used instead of a logical argument, or to obscure the fact that no compelling rational reason exists for one’s position. Appeals to emotion are a very common and effective argument tactic, but they’re ultimately flawed.

Appeal to Tradition (Logical Fallacy) – The fallacy that a point of view, situation, or action is right, proper and correct simply because it has “always” been that way, because people have “always” thought that way, or because it continues to serve one particular group very well.

Assumption – A thing that is accepted as true or as certain to happen, without proof; something that is taken for granted; a supposition.

Audio Pareidolia – The act of hearing words that are not actually there. This can occur by misinterpreting words that are being said, or by hearing words in random noise. The phenomenon is similar to visual pareidolia in that the brain, in searching for a recognized pattern, finds the closest match, and then processes the incoming sensory information to enhance the apparent match.

Autokinetic Effect – Refers to perceiving a stationary point of light in the dark as moving. Psychologists attribute the perception of movement where there is none to “small, involuntary movements of the eyeball” (Schick and Vaughn 1995: 47). The autokinetic effect can be enhanced by the power of suggestion: If one person reports that a light is moving, others will be more likely to report the same thing (Zusne and Jones).

Bandwagon (Logical Fallacy) – An appeal to popularity, or the fact that many people do something, as an attempted form of validation. Popularity of an idea has no bearing on its validity.

Barnum Effect – Named after P.T. Barnum, this is a product of people’s predilection to believe positive statements about themselves, even when there is no particular reason to do so. People will selectively notice the things which are preferable while ignoring those things which are not. Studies of how people receive astrological predictions have revealed the influence of the Barnum Effect.

Belief – Confidence in the truth of or existence of something not immediately susceptible to rigorous proof; an acceptance that a statement is true or that something exists; a firmly held opinion or conviction.

Belief-Bias Effect – Refers to the results that happen when an individual’s own values, beliefs, prior knowledge, etc. affects, or distorts the reasoning process through the acceptance of invalid arguments or data. This can happen when an observer assumes ahead of time that he knows what the results of an experiment will be and uses that belief to distort the results.

Belief Perseverance – The tendency to cling to one’s initial belief even after receiving new information that contradicts or disconfirms the basis of that belief; tendency or unwillingness to admit their foundational premises are incorrect even when shown convincing evidence to the contrary; tendency to persist with one’s held beliefs despite the fact that the information is inaccurate or that evidence shows otherwise.

Bias – A particular tendency or inclination, especially one that prevents unprejudiced consideration of a question; prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair.

Black or White (Logical Fallacy) – The presentation of only two alternative states as the only possibilities, when in fact more possibilities exist. Also known as the false dilemma, this insidious tactic has the appearance of forming a logical argument; it frames the argument misleadingly and obscures rational, honest debate.

Blind Loyalty (Logical Fallacy) – The dangerous fallacy that an argument or action is right simply and solely because a respected leader or source (an expert, parents, one’s own “side,” team or country, one’s boss or commanding officers) say it is right. This is over-reliance on authority, a corrupted argument from ethos that puts loyalty above truth or above one’s own reason and conscience.

Blood is Thicker than Water (Logical Fallacy) – The reverse of the “Ad Hominem” fallacy, a corrupt argument from ethos where a statement, argument or action is automatically regarded as true, correct and above challenge because one is related to, or knows and likes, or is on the same team as the individual involved.

Bullying – Unwanted, aggressive behavior typical among school-aged children that involves a real or perceived power imbalance. The behavior is repeated, or has potential to be repeated, over time. Bullying includes actions such as making threats, spreading rumors, attacking someone physically or verbally, and excluding someone from a group.

Burden of Proof – A responsibility for supporting a claim with valid evidence.  This responsibility rests with the person who is making a claim, and NOT upon anyone else to disprove. The inability, or disinclination, to disprove a claim does not render the original claim valid, nor give it any credence. Value to any claim is assigned via the available evidence, but to dismiss something on the basis that it hasn’t been proven beyond all doubt is fallacious reasoning.

Calibrate – To correlate the readings of (an instrument) with those of a standard in order to check the instrument’s accuracy.

Camera Shake – The camera moves while the shutter is open resulting in motion blur in the photos.

Cargo Cult Science – A term first used by physicist Richard Feynman during his commencement address at the California Institute of Technology, United States, in 1974, to negatively characterize research in the soft sciences (psychology and psychiatry in particular) arguing that they have the semblance of being scientific, but are missing “a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty”. The phrase is based on a concept in anthropology, the cargo cult, which describes how some pre-scientific cultures interpreted technologically advanced visitors as religious or supernatural figures who brought boons of cargo. Later, in an effort to call for a second visit the natives would develop and engage in complex religious rituals, mirroring the previously observed behavior of the visitors manipulating their machines but without understanding the true nature of those tasks. Just as cargo cultists created mock airports that fail to produce airplanes, cargo cult scientists conduct flawed research that superficially resembles the scientific method, but which fails to produce scientifically useful results.

Case Study – An in-depth study of a single research participant or event.

Causality – The relationship between cause and effect; the connection between two events or states such that one produces or brings about the other where one is the cause and the other is the effect; the principle that everything has a cause.

Chance – The possibility of something happening; the occurrence and development of events in the absence of any obvious design; something that happens unpredictably without discernible human intention or observable cause; the possibility of a particular outcome in an uncertain situation; the degree of likelihood of such an outcome.

Claim – To state or assert that something is the case, often without providing evidence or proof; an assertion of the truth of something, typically one that is disputed or in doubt; to assert or maintain as a fact.

Clarify – To check that both the speaker and listener are of the same understanding; to make (a statement or situation) less confused and more clearly comprehensible.

Closed-Minded (or close-minded) – Having or showing rigid opinions or a narrow outlook; obstinately resistant to argument or to unfamiliar or unwelcome ideas; having a mind firmly unreceptive to new ideas or arguments.

Conditioning – Also known as classical conditioning or Pavlovian conditioning, a form of learning and expectation based on the experience of association between a stimulus and a response.

Cognitive – Of or pertaining to the mental processes of perception, memory, judgment, and reasoning, as contrasted with emotional and volitional processes; conscious mental activities: the activities of thinking, understanding, learning and remembering.

Cognitive Dissonance – Mental conflict that occurs when beliefs or assumptions are contradicted by new information. The concept was introduced by the psychologist Leon Festinger (1919–89) in the late 1950s. He and later researchers showed that, when confronted with challenging new information, most people seek to preserve their current understanding of the world by rejecting, explaining away, or avoiding the new information or by convincing themselves that no conflict really exists.

Coincidence – A striking occurrence of two or more events at one time apparently by mere chance. The occurrence of events at the same time by accident, but seem to have some connection.

Cold Reading – A series of techniques used by mentalists, psychics, mediums, fortune tellers and illusionists to determine or express personal details of another person, often in order to convince someone that the reader knows a great deal more about a person (mark) than they actually do. Cold Readers use high probability guesses about the subject, quickly picking up on unconscious signals from their subjects as to whether guesses are in the right direction or not. They emphasize and reinforce chance connections the subject acknowledges while quickly moving pass missed guesses.

Complex Question, The (Logical Fallacy) – The fallacy of demanding a direct answers to a question that cannot be answered without first analyzing or challenging the basis of the question itself. Also applies to situations where one is forced to either accept or reject complex standpoints or propositions containing both acceptable and unacceptable parts.

Conclusion – A judgment or decision reached by reasoning. The last step in a reasoning process; judgment, decision, or opinion formed after investigation or thought.

Cones – Receptor cells concentrated near the center of the retina responsible for color vision and fine detail; most sensitive in brightly lit areas.

Confabulation – In psychology, a memory disturbance, defined as the production of fabricated, distorted or misinterpreted memories about oneself or the world, without the conscious intention to deceive. Confusion of an event that happened to someone else with one that happened to you, or a belief that you remember something when it never actually happened. In psychiatry, it is the replacement of a gap in a person’s memory by a falsification that he or she believes to be true, to fill in gaps in memory by fabrication.

Confirmation Bias – A phenomenon wherein decision makers have been shown to actively seek out and assign more weight to evidence that confirms their hypothesis, and ignore or under weigh evidence that could disconfirm their hypothesis. It is a tendency to search for and interpret information in a way that confirms one’s preconceptions, leading to statistical errors. As such, it can be thought of as a form of selection bias in collecting evidence.

Contagion (Psychology) – The spread of a behavior pattern, attitude, or emotion from person to person or group to group through suggestion, propaganda, rumor or imitation.

Continuous Reinforcement – A reinforcement schedule in which a particular response is always reinforced.

Control – An experiment or observation designed to minimize the effects of variables other than the single independent variable. This increases the reliability of the results, often through the comparison between control measurements and other measurements. Ideally, all variables in an experiment will be controlled.

Correlation – A mutual relationship or connection between two or more things; the relationship between things that happen or change together; a measure of how strongly two variables are related to each other.

Correlation Does Not Imply Causation – A phrase in science and statistics that emphasize that a correlation between two variables does not necessarily imply that one causes the other.

Credulous – Having or showing too great a readiness to believe things; willing to believe or trust too readily, especially without proper or adequate evidence; gullible.

Critical Thinking – The identification and evaluation of evidence to guide decision making. A critical thinker uses a broad in-depth analysis of evidence to make decisions and communicate beliefs clearly and accurately. Critical thinking is that mode of thinking — about any subject, content, or problem — in which the thinker improves the quality of his or her thinking by skillfully analyzing, assessing, and reconstructing it. Critical thinking is self-directed, self-disciplined, self-monitored, and self-corrective thinking. It presupposes assent to rigorous standards of excellence and mindful command of their use. It entails effective communication and problem-solving abilities, as well as a commitment to overcome our native egocentrism and sociocentrism.

Critical Thinker – A person who has the following qualities:

  • Is open-minded and mindful of alternatives
  • Desires to be, and is, well informed
  • Judges well the credibility of sources
  • Identifies reasons, assumptions and conclusions
  • Asks appropriate clarifying questions
  • Judges well the quality of an argument, including its reasons, assumptions, evidence, and their degree of support for the conclusion
  • Can well develop and defend a reasonable position regarding a belief or an action, doing justice to challenges
  • Formulates plausible hypothesis
, plans and conducts experiments well
  • Defines terms in a way appropriate to the context
  • Draws conclusions when warranted, but with caution

Cross Modulation – An effect that affects receivers used for amplitude modulation or vestigial sideband, or other forms of modulation where there is an amplitude component. Cross modulation traditionally occurred in receivers receiving an AM signal in the presence of other strong AM signals. It was found that the modulation from the strong signal was cross modulated and appeared on the weaker signal being received. Effectively, cross modulation is the transfer of modulation from one signal, typically a much stronger one, to another signal, typically a weaker one. AM broadcast receivers -This is traditionally the area where cross modulation effects had been noticed. When listing to weaker AM broadcast signals in the presence of very strong off channel signals, the modulation of the stronger signal or signals was transposed onto the weaker wanted signal. When broadcast receivers were located close to a broadcast transmitter, it could become an annoying problem.

Cryptozoology – A field of research of mostly amateurs involving the search for animals whose existence has not been proven. The animals cryptozoologists study are often referred to as cryptids, a term coined by John Wall in 1983. This includes looking for living examples of animals that are considered extinct, such as non-avian dinosaurs; animals whose existence lacks physical evidence but which appear in myths, legends, or are reported, such as Bigfoot and Chupacabra, and wild animals dramatically outside their normal geographic ranges, such as African big cats.

Cynic – A person who believes that only selfishness motivates human actions and who disbelieves in or minimizes selfless acts or disinterested points of view. They express a bitter or sneering attitude.

Cynical – Being concerned only with one’s own interests and typically disregards accepted or appropriate standards in order to achieve them. It is being contemptuous (scornful) and mocking.

Dark Adaptation– The adjustment of the eye to low light intensities, involving reflex dilation of the pupil and activation of the rod cells in preference to the cone cells. Rhodopsin, a biological pigment in the photoreceptors of the retina, immediately photobleaches in response to light. Rods are more sensitive to light and so take longer to fully adapt to the change in light. Rods, whose photopigments regenerate more slowly, do not reach their maximum sensitivity for about half an hour. Cones take approximately 9–10 minutes to adapt to the dark.

Data – Facts and statistics collected together for reference or analysis; individual facts, statistics, or items of information for an assessment.

Decline Effect – The notion that psychics lose their powers under continued investigation. This idea is based on the observation that subjects who do significantly better than chance in early trials tend to do worse in later trials. The term was first described by parapsychologist Joseph Banks Rhine in the 1930s to describe the disappearing of extrasensory perception (ESP) of psychic experiments conducted by Rhine over the course of study or time. The term was once again used in a 2010 article by Jonah Lehrer published in The New Yorker.

Deductive Reasoning – A form of reasoning in which a conclusion follows necessarily from certain premises; if the premises are true, the conclusion must be true.

Dependent Variable – A variable that an experimenter predicts will be affected by manipulation of the independent variable.

Depth of Field – The range of distance that appears acceptably sharp. It varies depending on camera type, aperture and focusing distance, although print size and viewing distance can also influence our perception of depth of field. The depth of field does not abruptly change from sharp to unsharp, but instead occurs as a gradual transition. In fact, everything immediately in front of or in back of the focusing distance begins to lose sharpness — even if this is not perceived by our eyes or by the resolution of the camera.

Delusions – Mistaken beliefs maintained in spite of strong evidence to the contrary.

Dismissive – Resulting from or showing lack of knowledge or intelligence.

Divination – The practice of seeking knowledge of the future or the unknown by supernatural means. The attempt to foretell the future or discover occult knowledge by interpreting omens or by using paranormal or supernatural powers.

Double Blind Study – An experiment in which neither the participants nor the individuals running the study know which participants are in the control group and which are in the experimental group until after the results are tallied.

Egocentric Thinking – Seeing the world from only your own point of view; the inability to take another person’s perspective.

Electrical Noise – Any unwanted electrical signals that may be picked up from other equipment that is unintentionally radiating (transmitting) them, or the unwanted signals can be generated within the equipment by less than perfect components. The term “noise” is used because the effect is similar to how audio noise prevents you from clearly hearing a sound or music you are trying to hear. Electrical noise is any kind of electrical energy that you do not want. For example, if you tune your radio to a place between two broadcasting stations, you may hear some static or bleed through from nearby stations.

Electromagnetic Spectrum – Abbreviated as EM, and also called spectrum or electromagnetic radiation spectrum, electromagnetic spectrum refers to the complete range of wavelengths of electromagnetic radiation. The electromagnetic spectrum includes the following different types of radiation (from lowest energy to highest): radio, microwaves, infrared, visible, ultraviolet, X-rays and gamma-rays.

Empirical – Relying on or derived from observation, experimentation, or measurement.

Energy – Energy is the ability to bring about change or to do work. Energy exists in many forms, such as heat, light, chemical energy, and electrical energy. Thermodynamics is the study of energy.

Evidence – The available body of facts or information indicating whether a belief or proposition is true or valid, that which tends to prove or disprove something.

EXIF – Stands for “exchangeable image file format”. It allows you to store certain information within your photographs. This information is known as “metadata” and can include things like the date and time the shot was taken, camera settings like shutter speed and focal length, and copyright information. This can be immensely useful when you’re reviewing your pictures. For example, you might notice that a shot of a runner has turned out a bit blurry, so you can examine the metadata to check your shutter speed, aperture, ISO speed and so on, and decide how you could do things differently in future.

Expectation – A strong belief that something will happen or be the case in the future. An expectant mental attitude. The act or state of looking forward or anticipating.

Experience – The involvement in something over time: active involvement in an activity or exposure to events or people over a period of time that leads to an increase in knowledge or skill. Knowledge or skill acquired: knowledge or skill gained through being involved in or exposed to something over a period of time.

Experiment – A scientific procedure undertaken to make a discovery, test a hypothesis, or demonstrate a known fact.

Experimenter Effect – An influence exerted by the experimenter’s expectations or other characteristics on the results of an experiment, especially in psychology. An effect on subjects due to the actions or presence of an experimenter.

Extrasensory Perception – (ESP) Perceptual, or “psychic”, abilities that supposedly go beyond the normal senses, including telepathy, clairvoyance, precognition, and psychokinesis.

Fact – A truth known by actual experience or observation; something known to be true. A thing that is indisputably the case; something that has actual existence; a piece of information presented as having objective reality.

Factoid – Unreliable information: something that may not be true but is widely accepted as true because it is repeatedly quoted, especially in the media.

Fake – Something that is not genuine, it is a forgery or sham, counterfeit. Something that is prepared or made in order to deceive.

False Analogy (Logical Fallacy) – The fallacy of incorrectly comparing one thing to another in order to draw a false conclusion.

False Cause (Logical Fallacy) – You presumed that a real or perceived relationship between things means that one is the cause of the other. Many people confuse correlation (things happening together or in sequence) for causation (that one thing actually causes the other to happen). Sometimes correlation is coincidental, or it may be attributable to a common cause.

Fraud – Wrongful or criminal deception intended to result in financial or personal gain; a person or thing intended to deceive others, typically by unjustifiably claiming or being credited with accomplishments or qualities; deceit, trickery, sharp practice, or breach of confidence, perpetrated for profit or to gain some unfair or dishonest advantage.

Frequency – The number of complete oscillations per second of energy (as sound or electromagnetic radiation) in the form of waves. Frequency describes the number of waves that pass a fixed place in a given amount of time. So if the time it takes for a wave to pass is 1/2 second, the frequency is 2 per second. If it takes 1/100 of an hour, the frequency is 100 per hour. Usually frequency is measured in the hertz unit, named in honor of the 19th-century German physicist Heinrich Rudolf Hertz.

Gauss – (symbolized by G) is the centimeter-gram-second (cgs) unit of magnetic flux density. A flux density of 1 G represents one Maxwell per centimeter squared (1 Mx cm-2). The guass was named for the German scientist Karl Friedrich Gauss. The gauss is used when expressing the flux density produced by magnets of the sort commonly encountered in consumer products. The flux density of the earth’s magnetic field at the surface is about 1 G. In industrial electromagnetics, the tesla (T), a much larger unit, is used to express magnetic flux density. The gauss is equal to one ten-thousandth of a tesla.

Genetic Fallacy (Logical Fallacy) – Judging something as either good or bad on the basis of where it comes from, or from whom it came. This fallacy avoids the argument by shifting focus onto something’s or someone’s origins. It’s similar to an ad hominem fallacy in that it leverages existing negative perceptions to make someone’s argument look bad, without actually presenting a case for why the argument itself lacks merit.

Groupthink – In close-knit groups, the tendency for all members to think alike for the sake of harmony and to suppress disagreement. The practice of thinking or making decisions as a group in a way that discourages creativity or individual responsibility. A psychological phenomenon that occurs within a group of people, in which the desire for harmony or conformity in the group results in an irrational or dysfunctional decision-making outcome. Faulty decision making that occurs when a highly cohesive group strives for agreement and avoids inconsistent information.

Half Truth (Logical Fallacy) – the fallacy of telling the truth but deliberately omitting important key details in order to falsify the larger picture and support a false conclusion.

Hallucination – An experience involving the apparent perception of something not present. A perception of something (as a visual image or a sound) with no external cause usually arising from a disorder of the nervous system (as in delirium tremens or in functional psychosis without known neurological disease) or in response to drugs; perceiving things in the absence of stimulation; perceiving things that are not really there. A hallucination can be false or distorted, but seem very real and vivid to the person experiencing it. Hallucinations can involve any of the senses including vision, hearing, smell, touch, taste and movement. There are a number of different things that may cause hallucinations including substance abuse and schizophrenia.

Hate Group – An organized group or movement that advocates and practices hatred, hostility, or violence towards members of a race, ethnicity, religion, gender, gender identity, sexual orientation or any other designated sector of society. According to the United States Federal Bureau of Investigation (FBI), a hate group’s “primary purpose is to promote animosity, hostility, and malice against persons belonging to a race, religion, disability, sexual orientation, or ethnicity/national origin which differs from that of the members of the organization.” The Southern Poverty Law Center’s (SPLC) definition of a “hate group” includes those having beliefs or practices that attack or malign an entire class of people, typically for their immutable characteristics.

Hertz – The measurement, abbreviated Hz, is the number of waves that pass by per second. For example, an “A” note on a violin string vibrates at about 440 Hz (440 vibrations per second).

Hindsight Bias – The tendency to overestimate one’s ability to have predicted an event once the outcome is known. Also known as the knew-it-all-along effect or creeping determinism, it is the inclination, after an event has occurred, to see the event as having been predictable, despite there having been little or no objective basis for predicting it, prior to its occurrence.

Hoax – Something intended to deceive or defraud. A trick into believing or accepting as genuine something false and often preposterous. They are done deliberately, and not from a mistake or accident.

Hot Reading – A technique used when giving a psychic reading in stage magic performances, or in other contexts. In hot reading, the reader uses information about the person receiving the reading (for example, from background research or overhearing a conversation) which the receiver is not aware that the reader already knows. Hot reading is commonly used in conjunction with cold reading (where no previously gathered information is used) and can explain how a psychic reader can get a specific claimed “hit” of accurate information.

Hypothesis – An educated guess, based on observation. Usually, a hypothesis can be supported or refuted through experimentation or more observation. A hypothesis is a propostion, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either as a provisional conjecture to guide investigation (working hypothesis) or accepted as highly probable in the light of established facts. These reasoned explanations are not guesses — of the wild or educated variety. When scientists formulate new hypotheses, they are usually based on prior experience, scientific background knowledge, preliminary observations, and logic.

Ideomotor Effect – Refers to the influence of suggestion or expectation on involuntary and unconscious motor behavior. The movement of pointers on Ouija boards, of a facilitator’s hands in facilitated communication, of hands and arms in applied kinesiology, and of some behaviors attributed to hypnotic suggestion, are due to ideomotor action. The term “ideomotor action” was coined by William B. Carpenter in 1852 in his explanation for the movements of rods and pendulums by dowsers, and some table turning or lifting by spirit mediums (the ones that weren’t accomplished by cheating). Scientific tests by American psychologist William James, French chemist Michel Chevreul, English scientist Michael Faraday (Zusne and Jones 1989: 111), and American psychologist Ray Hyman have demonstrated that many phenomena attributed to spiritual or paranormal forces, or to mysterious “energies,” are actually due to ideomotor action. Furthermore, these tests demonstrate that “honest, intelligent people can unconsciously engage in muscular activity that is consistent with their expectations” (Hyman 1999). They also show suggestions that guide behavior can be given by subtle cues (Hyman 1977).

Ignorance (Ignorant) – Lacking knowledge or awareness in general; uneducated or unsophisticated; lacking knowledge, information, or awareness about something in particular; resulting from or showing lack of knowledge or intelligence.

Implicit Learning – Learning that occurs when you acquire knowledge about something without being aware of how you did so and without being able to state exactly what it is you have learned.

Imply – To express something in an indirect way without saying it plainly. The speaker implies.

Independent Variable – A variable that an experimenter manipulates.

Infer – To form an opinion based on evidence and reasoning; the listener infers.

Informational Social Influence – Conforming to group pressure out of a need for direction or information.

Infrared (of Electromagnetic Radiation) – Having a wavelength just greater than that of the red end of the visible light spectrum but less than that of microwaves. Infrared radiation has a wavelength from about 800 nm to 1 mm, and is emitted particularly by heated objects.

Interpretation – The act or result of explaining or interpreting something; the way something is explained or understood.

Investigate – To carry out a systematic or formal inquiry to discover and examine the facts of an incident, allegation, claim, etc. so as to establish the truth; carry out research or study into a subject, typically one in the scientific or academic field, so as to discover facts or information; to examine, study or inquire into systematically; search or examine into the particulars of; examine in detail.

Investigation – The act or process of investigating (see “Investigate”) or the condition of being investigated. A searching inquiry for ascertaining facts; detailed or careful examination.

Investigator – A person who investigates (see “Investigate”). A person who carries out a formal inquiry or investigation. A person whose job is to examine a crime, problem, statement, claim, etc. in order to discover the truth.

ISO – Short for International Standards Organization, and sometimes referred to by its former name “ASA,” ISO is a numerical representation of the imaging devices’ sensitivity to light. In traditional (film) photography ISO (or ASA) was the indication of how sensitive a film was to light. It was measured in numbers (you’ve probably seen them on films – 100, 200, 400, 800 etc.). The lower the number the lower the sensitivity of the film and the finer the grain in the shots you’re taking. In Digital Photography ISO measures the sensitivity of the image sensor. The same principles apply as in film photography – the lower the number the less sensitive your camera is to light and the finer the grain. Higher ISO settings are generally used in darker situations to get faster shutter speeds. For example, an indoor sports event when you want to freeze the action in lower light. However the higher the ISO you choose, the “noisier” shots you will get.

Knowledge – known information; general awareness or possession of information, facts, ideas, truths, or principles; specific information; clear awareness or explicit information

Law of Conservation of Energy – The first law of thermodynamics which states that the total amount of energy in a system remains constant (“is conserved”), although energy within the system can be changed from one form to another or transferred from one object to another. Energy cannot be created or destroyed, but it can be transformed. This is really what we mean when we say we are “using” energy. The law of conservation of energy means that when energy is being used, it is not being used up. Instead, it is being changed from one form into another. A car engine burns fuel, converting the fuel’s chemical energy into mechanical energy to make the car move. Windmills change the wind’s energy into mechanical energy to turn turbines, which then produce electricity. Solar cells change sunlight (radiant energy) into electrical energy.

Lens Flare – An anomaly created when non-image forming light enters the lens and subsequently hits the camera’s film or digital sensor. This often appears as a characteristic polygonal shape, with sides which depend on the shape of the lens diaphragm. It can lower the overall contrast of a photograph significantly and is often an undesired artifact, however some types of flare may actually enhance the artistic meaning of a photo. Flare can take many forms, and this may include just one or all of the polygonal shapes, bright streaks, or overall washed out look (veiling flare).

Light Adaptation – The reflex adaptation of the eye to bright light, consisting of an increase in the number of functioning cones, accompanied by a decrease in the number of functioning rods (opposed to dark adaptation); the adjustment of the eye under increased illumination, in which the sensitivity to light is reduced; the process for light adaptation occurs over a period of five minutes.

Literally – In a literal or strict sense, i.e. something that really happened, without exaggeration or inaccuracy. Often misused adverb.

Loaded Question (Logical Fallacy) – One asks a question that has a presumption built into it so that it couldn’t be answered without implication. Loaded question fallacies are particularly effective at derailing rational debates because of their inflammatory nature – the recipient of the loaded question is compelled to defend himself and may appear flustered.

Logic – A proper or reasonable way of thinking about or understanding something. It is the study of the principles of correct reasoning, the main principle of which is whether certain conclusions follow from some given assumptions.

Logical Fallacy – A flaw in the structure of a deductive argument which renders the argument invalid. Logic is the use of valid reasoning; a fallacy is an argument that uses poor reasoning.

Long Exposure – Long-exposure photography, or time-exposure photography, involves using a long-duration shutter speed to sharply capture the stationary elements of images while blurring, smearing, or obscuring the moving elements. The paths of moving light sources become clearly visible.

Magical Thinking – Believing that one event happens as a result of another without a plausible link of causation; belief that merely thinking about an event in the external world can cause it to occur. It may be part of ideas of reference, considered normal in those instances, or may reach delusional proportions when the individual maintains a firm conviction about the belief, despite evidence to the contrary. The erroneous belief, similar to a normal stage of childhood development—Piaget’s pre-operational phase—that thoughts assume a magical power capable of influencing events without a physical action actually occurring; a conviction that thinking equates with doing, accompanied by an unrealistic understanding of cause and effect.

Matrixing – An electronic method of processing quadraphonic sound for recording in a two-channel form, for reconversion to four channels when played back.

Medium – The intervening substance through which impressions are conveyed to the senses or a force acts on objects at a distance. A person supposedly used as a spiritual intermediary between the dead and the living.

MilliGauss (mG) – One milliGauss is 1/1000 of a Gauss (see Gauss).

Misinformation Effect – Incorporation of incorrect information (misinformation) into our memory of an eyewitness event. The result is an altered memory of the event. Human memory is just not as good as people think it is. Misinformation can also creep in by how a question is phrased.

Motion Blur – Apparent streaking of rapidly moving objects in a still image or a sequence of images such as a movie or animation. It results when the image being recorded changes during the recording of a single frame, either due to rapid movement or long exposure.

Moving the Goalposts (Logical Fallacy) – Demanding an opponent to address more and more points after the initial counter-argument has been satisfied, refusing to conceded or accept the opponent’s argument; previously agreed upon standards for deciding an argument are arbitrarily changed once they have been met. This is usually done by the “losing” side of an argument in a desperate bid to save face. If the goalposts are moved far enough, then the standards can eventually evolve into something that cannot be met no matter what (or anything will meet said standard if the losing side is trying to meet the standard using this tactic). Also known as: gravity game, raising the bar, argument by demanding impossible perfection.

No True Scotsman (Logical Fallacy) – One makes what could be called an Appeal to Purity as a way to dismiss relevant criticisms or flaws of your argument. In this form of faulty reasoning, one’s belief is rendered unfalsifiable because no matter how compelling the evidence is, one simply shifts the goalposts so that it wouldn’t apply to a supposedly ‘true example’. This kind of post-rationalization is a way of avoiding valid criticism of one’s argument.

Null Hypothesis – A type of hypothesis used in statistics that proposes no statistical significance exists in a set of given observations. The null hypothesis attempts to show that no variation exists between variables, or that a single variable is no different than zero. It is presumed to be true until statistical evidence nullifies it for an alternative hypothesis. The null hypothesis assumes that any kind of difference or significance you see in a set of data is due to chance. Scientific hypothesis must show evidence sufficient to reject the null hypothesis.

Objective – Not influenced by personal feelings or opinions in considering and representing facts.

Observation – The active acquisition of information from a primary source. In living beings, observation employs the senses. In science, observation can also involve the recording of data via the use of instruments. The term may also refer to any data collected during the scientific activity.

Occam’s Razor – A scientific and philosophic rule that entities should not be multiplied unnecessarily which can be interpreted as requiring that the simplest of competing theories be preferred to the more complex, or that explanations of unknown phenomena be sought first in terms of known quantities.

Open-Minded – A willingness to try new things or to hear and consider new ideas; to be receptive to arguments or ideas. Willing to consider new ideas; unprejudiced.

Operational Definition – A precise definition of a term in a hypothesis, which specifies the operations for observing and measuring the process or phenomenon being defined; a belief or judgment that rests on grounds insufficient to produce complete certainty.

Opinion – A personal view; the view somebody takes about an issue, especially when it is based solely on personal judgment.

Patternicity -The tendency to find meaningful patterns in both meaningful and meaningless noise.

Paranormal – Coined in 1920, it meant “beside, above or beyond normal”. By 1970, the term was expanded to include all mysterious phenomenon, including ghosts, UFOs, monsters, psychic powers, strange disappearances and claims that appear to be not of normal explanation.

Parapsychology – The study of purported psychic phenomenon such as ESP and mental telepathy.

Parasomnias – Refers to all the abnormal things that can happen to people while they sleep, apart from sleep apnea. Examples include sleep-related eating disorder, sleepwalking, nightmares, sleep paralysis, REM sleep behavior disorder, and sleep aggression. Parasomnias can occur as a person is falling asleep or at any point in the sleep cycle. If they occur while falling asleep, a person may experience disturbing hallucinations or sleep paralysis, which is when the body is unable to move for seconds or minutes. Sleep paralysis can be quite frightening, especially when it occurs with hallucinations. Parasomnias that occur during sleep, such as REM sleep behavior disorder (RBD), often involve vigorous and harmful dream-enacting behaviors.

Pareidolia – A type of illusion or misperception involving a vague or obscure stimulus being perceived as something clear and distinct. It often involves a sound or image being perceived as something significant. (Synonymous with “Matrixing”, a term coined by certain ghost hunters but has a distinctly different definition, see “matrixing”.)

Peer Review – Peer review is the evaluation of work by one or more people of similar competence to the producers of the work. It constitutes a form of self-regulation by qualified members of a profession within the relevant field. Peer review is the evaluation of creative work or performance by other people in the same field in order to maintain or enhance the quality of the work or performance in that field. It is based on the concept that a larger and more diverse group of people will usually find more weaknesses and errors in a work or performance and will be able to make a more impartial evaluation of it than will just the person or group responsible for creating the work or performance. Peer review is a crucial phase of scientific work.

Perception – The process by which the brain organizes and interprets sensory information. A reaction to a placebo manifested by a lessening of symptoms or the production of anticipated side effects.

Personal Incredulity (Logical Fallacy) – Results when a person finds something difficult to understand, or are unaware of how it works, and so assumes that it is probably not true. Complex subjects like biological evolution through natural selection requires some amount of understanding before one is able to make an informed judgment about the subject at hand; this fallacy can be used in place of that understanding.

Phrenology – A now discredited theory that different brain areas account for a specific character and personality traits, which can be “read” from the bumps on the skull.

Placebo – An inactive substance or fake treatment used as a control in an experiment. A placebo is anything that seems to be a “real” medical treatment — but isn’t. It could be a pill, a shot, or some other type of “fake” treatment. What all placebos have in common is that they do not contain an active substance meant to affect health.

Placebo Effect – Any effect that seems to be a consequence of administering a placebo; the change is usually beneficial and is assumed result from the person’s faith in the treatment or preconceptions about what the experimental drug was supposed to do; pharmacologists were the first to talk about placebo effects but now the idea has been generalized to many situations having nothing to do with drugs. The effect includes all the unrecognized bias within the study, not just the effect due to the placebo itself.

Plausible – Seemingly or apparently valid, likely, or acceptable; apparently reasonable, truthful. It does not mean that something is definitely valid or truthful, just that it could be.

Post Hoc Argument (Logical Fallacy) – The classic fallacy that because something comes at the same time or just after something else, the first thing is caused by the second.

Priming – An acuteness to stimuli because of previous exposure to a certain event or experience. For example, an individual who purchases a new car may now start to notice with more frequency, other people driving the same make and model. This person has been primed to recognize more readily a car like their own because of the experience they have driving and owning one.

Premise – A proposition upon which an argument is based or from which a conclusion is formed – it’s the foundation you build your argument on. In order for an argument to be sound, all of its premises must be true.

Preternatural – That which appears outside or beside the natural; beyond what is normal or natural; existing outside of nature; apparently inexplicable by natural means.

Probability – The extent to which something is probable; the likelihood of something happening or being the case; the chance that a given event will occur.

Professional – A person engaged in a specified activity as one’s main paid occupation rather than as a pastime; a person engaged or qualified in a profession; a person formally certified by a professional body or belonging to a specific profession by virtue of having completed a required course of studies and/or practice and whose competence can usually be measured against an established set of standards; a person who has achieved an acclaimed level of proficiency in a calling or trade.

Proof – Evidence that establishes existence or truth (or non-existence or untruth) of a fact to the satisfaction of an authority (such as a court) or according to the accepted standards. Scientific proof is based on empirical evidence.

Psychic – Relating to or denoting faculties or phenomena that are apparently inexplicable by natural laws, especially involving telepathy or clairvoyance;  a person appearing or considered to have powers of telepathy or clairvoyance.

Puberty – The period during which adolescents reach sexual maturity and become capable of reproduction; the condition of being or the period of becoming first capable of reproducing sexually marked by maturing of the genital organs, development of secondary sex characteristics, and in the human and in higher primates by the first occurrence of menstruation in the female.

Quantum Physics – The study of the behavior of matter and energy at the molecular, atomic, nuclear, and even smaller microscopic levels. In the early 20th century, it was discovered that the laws that govern macroscopic objects do not function the same in such small realms.
Random – made, done, happening, or chosen without method or conscious decision. Governed by or involving equal chances for each item.

Red Herring (Logical Fallacy) – An irrelevant distraction, attempting to mislead an audience by bringing up an unrelated, but usually emotionally loaded issue.

Reflection – The throwing back by a body or surface of light, heat, or sound without absorbing it

Refute – Prove a statement or theory to be wrong or false, disprove; to prove wrong by argument or evidence, show to be false or erroneous; to deny the truth or accuracy of.

Refraction – The change of direction of a ray of light, sound, heat, or the like, in passing obliquely from one medium into another in which its wave velocity is different.

Regulate – To control or supervise (something, especially a company or business activity) by means of rules and regulations; to adjust so as to ensure accuracy of operation.

Research – The systematic investigation into and study of materials and sources in order to establish facts and reach new conclusions; careful study that is done to find and report new knowledge about something

Retinal – Light-sensitive inner surface of the back of the eye, which contains the receptive cells for vision (cones and rods).

Rods – Receptor cells in the retina that detect shades of gray, are responsible for peripheral vision, and are most sensitive in dim light.

Science – The intellectual and practical activity encompassing the systematic study of the structure and behavior of the physical and natural world through observation and experiment; the community of those who use this method to procure knowledge; the body of reliable knowledge derived about a certain topic in nature.

Scientifical – Attempting to be scientific but falling short of achieving credible research; use of science-like jargon and imagery to make yourself sound intelligent to a lay audience when you have no idea what you are talking about.

Scientific Method – A method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement and experiment, and the formation, testing, and modification of hypotheses. There is no “cookbook” scientific method but best practices vary for each scientific field.

Selective Thinking – The process whereby one selects favorable evidence for remembrance and focus, while ignoring unfavorable evidence for a belief; the process by which one focuses on favorable evidence in order to justify a belief, ignoring unfavorable evidence. (See also Confirmation Bias)

Self-Proclaimed – Described as or proclaimed to be such by oneself, without endorsement by others; giving yourself a particular name, title, etc. usually without any reason or proof that would cause other people to agree with the proclamation.

Self-Serving Bias – Taking credit for our successes and externalizing our failures.

Shutter – A curtain in front of the camera sensor that stays closed until the camera fires. When the camera fires, the shutter opens and fully exposes the camera sensor to the light that passes through the lens aperture. After the sensor is done collecting the light, the shutter closes immediately, stopping the light from hitting the sensor. The button that fires the camera is also called “shutter” or “shutter button”, because it triggers the shutter to open and close.

Shutter Speed (Exposure Time) – The amount of time that the shutter is open. Shutter speed is measured in seconds – or in most cases fractions of seconds. The bigger the denominator, the faster the speed (i.e., 1/1000 is much faster than 1/30). Shutter speed, also known as “exposure time”, represents the length of time a camera shutter is open to expose light into the camera sensor. If the shutter speed is fast, it can help to freeze action completely. If the shutter speed is slow, it can create an effect called “motion blur”, where moving objects appear blurred along the direction of the motion.

Skeptic – A person who questions the validity or authenticity of something purporting to be factual, such as a claim or statement. A modern participant in the “skeptic” community seeks conclusions solely on the basis of the best evidence derived for a claim.

Skepticism – The process of applying reason and critical thinking to determine validity – finding a supported conclusion, not the justification of a preconceived conclusion. Skepticism is not a position; it’s a process. Expression of being not easily convinced, having doubts or reservations; practice of doubting or having a questioning attitude or state of mind; a methodology based on an assumption of doubt with the aim of acquiring approximate or relative certainty.

Sleep Paralysis – A feeling of being conscious but unable to move. It occurs when a person passes between stages of wakefulness and sleep. During these transitions, you may be unable to move or speak for a few seconds up to a few minutes. Some people may also feel pressure or a sense of choking. A frightening form of paralysis that occurs when a person suddenly finds himself or herself unable to move for a few minutes, most often upon falling asleep or waking up. Sleep paralysis is due to an irregularity in passing between the stages of sleep and wakefulness. The symptoms of sleep paralysis include sensations of noises, smells, levitation, paralysis, terror, and images of frightening intruders. Once considered very rare, up to half of all people are now believed to experience sleep paralysis sometime during their life. Sleep paralysis is not considered to be a sign of a serious condition, although it can be frightening. Sleep paralysis occurs as a person is moving into or out of REM (rapid eye movement) sleep, the deepest part of sleep. During REM sleep, the body is largely disconnected from the brain, effectively leaving the body paralyzed. Sleep paralysis is the result of premature (or persistent) mind-body disconnection as one is about to enter into (or exit from) REM sleep.

Slippery Slope (Logical Fallacy) – States that if we allow “A” to happen, then “Z” will eventually happen too, therefore “A” should not be allowed to happen. The problem with this reasoning is that it avoids engaging with the issue at hand, and instead shifts attention to extreme hypotheticals. Because no proof is presented to show that such extreme hypotheticals will in fact occur, this fallacy has the form of an Appeal to Emotion fallacy by leveraging fear. In effect the argument at hand is unfairly tainted by unsubstantiated conjecture.

Special Pleading (Logical Fallacy) – To “move the goalposts” or made up an exception when a personal claim was shown to be false. Humans have an aversion to being wrong. Rather than appreciate the benefits of being able to change one’s mind through better understanding, many will invent ways to cling to old beliefs. One of the most common ways that people do this is to post-rationalize a reason why what they thought to be true must remain to be true.

Spotlight Effect – A term used by social psychologists to refer to the tendency to overestimate how much other people notice about us: our appearance, our behavior, and in particular for those with social anxiety disorder (SAD), our social faux pas. It is named the spotlight effect, because you operate as though a spotlight is shining on you and believe others are paying more attention to you than they actually are.

Statistical Significance – A result that is not likely to occur randomly, but rather is likely to be attributed to a specific cause. Statistical significance can be strong or weak, and is important to scientific research including in medicine, sociology, psychology and biology. Statistical significance does not always indicate practical significance. In addition, it can be misinterpreted when researchers do not use language carefully in reporting their results.

Strawman (Logical Fallacy) – Misrepresenting someone’s argument to make it easier to attack. By exaggerating, misrepresenting or just completely fabricating someone’s argument, it’s much easier to present your own position as being reasonable, but this kind of dishonesty serves to undermine honest rational debate.

Subjective – Based on or influenced by personal feelings, tastes or opinions. Relating to the way a person experiences things in his or her own mind.

Subjective Validation – Refers to a process by which people accept some claim or phenomenon as valid based solely upon a few personal experiences and/or subjective perception.

Subliminal – Pertaining to any stimulus presented below the threshold of conscious awareness.

Supernatural – A manifestation or event attributed to some force beyond scientific understanding or the laws of nature; of or relating to an order of existence beyond the visible observable universe; manifestations or events considered to be of supernatural origin, such as ghosts.

Theory (Scientific Theory) – Summarizes a hypothesis or group of hypotheses that have been supported with repeated testing; an accepted hypothesis. A theory is valid as long as there is no evidence to dispute it. Therefore, theories can be disproven. If evidence accumulates in support of a hypothesis, then the hypothesis will become accepted as a good explanation of a phenomenon. They are concise (i.e., generally don’t have a long list of exceptions and special rules), coherent, systematic, predictive, and broadly applicable.
 *”It’s just a theory” – Occasionally, scientific ideas are written off with the putdown “it’s just a theory”. This slur is misleading and conflates two separate meanings of the word theory: in common usage, the word theory means just a hunch, but in science, a theory is a powerful explanation for a broad set of observations, a model of how the world works.

Thermodynamics – The branch of physical science that deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.

True-Believer Syndrome – An expression coined by M. Lamar Keene to describe an apparent cognitive disorder characterized by believing in the reality of paranormal or supernatural events after one has been presented overwhelming evidence that the event was fraudulently staged.

Trust – Belief that someone or something is reliable, good, honest, effective, etc.

UFO – An unidentified flying object. In its most general definition, any apparent anomaly in the sky that is not identifiable as a known object or phenomenon. Such anomalies may later be identified, but depending on the evidence or lack of evidence, such an identification may not be possible generally leaving the anomaly unexplained. The term “UFO” (or “UFOB”) was officially created in 1953 by the United States Air Force (USAF) to serve as a catch-all for all such reports. It was stated that a “UFOB” was “any airborne object which by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identified as a familiar object.” As originally defined, the term was restricted to those fraction of cases which remained unidentified after investigation, with USAF interest being for potential national security reasons and/or “technical aspects.” (See Air Force Regulation 200-2.) During the late 1940s and through the 1950s, UFOs were often referred to popularly as “flying saucers” or “flying discs”. The term UFO became more widespread during the 1950s, at first in technical literature, but later in popular use. UFOs garnered considerable interest during the Cold War, an era associated with a heightened concern for national security. The term today is often associated with a conclusion that the anomaly is an alien spacecraft.

Ultraviolet – Pertaining to a band of electromagnetic radiation having wavelengths (from c. 5 to c. 400 nanometers) that are shorter than violet light.

Understanding – A mental grasp; comprehension. The power of comprehending, especially the capacity to apprehend general relations of particulars; the power to make experience intelligible by applying concepts and categories.

Validate – Check or prove the validity or accuracy of (something).

Validity Effect – The tendency of people to believe that a statement is true or valid simply because it has been repeated many times.

Variable – An element, feature, or factor that is liable to vary or change.

White noise – A type of noise that is produced by combining sounds of all different frequencies together; all of the imaginable tones that a human can hear combined together. The adjective “white” is used to describe this type of noise because of the way white light works. White light is light that is made up of all of the different colors (frequencies) of light combined together (a prism or a rainbow separates white light back into its component colors). In the same way, white noise is a combination of all of the different frequencies of sound. Because white noise contains all frequencies, it is frequently used to mask other sounds.