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A dictionary of psychology and counselling. Read a definition, follow a connection, and find the source behind it.
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Showing the first 60 terms. Use search or the alphabetical index to browse every entry.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
2-AG is an endogenous molecule called 2-arachidonoylglycerol that is normally broken down by the enzyme MGLL. When its levels rise, it increases cannabinoid receptor signaling in the central nervous system, which helps modulate neurotransmission and can reduce overactive neural signaling.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
2-arachidonoylglycerol (2-AG) is an endogenous endocannabinoid that helps activate cannabinoid receptors, especially CB1 in the central nervous system. Its levels are normally reduced by the enzyme MGLL, and when 2-AG increases, endocannabinoid signaling is strengthened, which can dampen excessive neurotransmitter release and neural activity.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
In logic, A is the symbol for a universal affirmative statement, meaning that something is said to be true of all members of a group. An example is a statement like “all men are mortal.”
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
A posteriori refers to ideas or reasoning that depend on experience. In this contrast, it is opposed to a priori thought and is associated with inductive reasoning rather than deduction from what is taken to be already given in the mind.
social
Candidate: drafted from the sources shown, not yet read by the two reviewers.
In this packet, abandonment means leaving an older person without needed care or support, typically by family members or institutional staff. It is presented as one form of elder abuse.
assessment
Candidate: drafted from the sources shown, not yet read by the two reviewers.
ABCL refers to the Adult Behavior Checklist, an assessment form for adults aged 18 to 59 that gathers information from people who know the adult well. It is used alongside the Adult Self-Report to evaluate adult behavioral and emotional problems across settings, with scores compared to age- and sex-based norms.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
The abducens nerve is the sixth cranial nerve. It begins in the pons and carries motor signals to the eye’s lateral rectus muscle, helping control side-to-side eye movement; injury to the nerve or its nucleus can impair horizontal eye movements.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
The abducens nucleus is a group of nerve cells in the pontine tegmentum that serves as the nucleus of the abducens nerve.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abilify is the brand name for aripiprazole, an atypical antipsychotic medication. It affects dopamine and serotonin activity in the brain and is used to help manage schizophrenia symptoms and acute manic or mixed episodes in bipolar I disorder.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Ability is the quality of being able to do something. It refers to a capacity that makes achievement or accomplishment possible or easier.
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Ablution is a washing rite performed before prayer. In the source, it is described as the act that precedes prayer at the five set times of day in orthodox Sunni Islamic practice.
diagnosis
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abnormal describes something that differs from what is considered the usual or expected norm. It can refer to a departure in state, position, structure, condition, behavior, or rules.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abnormal psychology is the branch of psychology concerned with mental processes and experiences that differ from what is considered usual or normal. In a broad sense, it covers unusual mental phenomena as well as disturbances, impairments, and forms of mental disorder.
diagnosis
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abnormality is a condition that differs from a person’s usual physical or mental state. In psychology or counselling, the term can be used for changes that are outside what is typical for that individual.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Aboulia is a loss or marked lack of the ability to use or exercise one’s will. It refers to a weakness of volition that can appear in different forms.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
ABPP refers to amyloid-beta precursor protein, a human protein made from the APP gene. It helps with receptor-related signaling at the cell surface and can be cut into several smaller products, including soluble peptides, membrane-bound fragments, components of amyloid plaques, regulatory molecules, and neurotoxic fragments.
assessment
Candidate: drafted from the sources shown, not yet read by the two reviewers.
ABR, or auditory brainstem response, is an objective neurological test that measures how the auditory nerve and brainstem pathways respond to sound. It is used to assess hearing-related nerve pathways and to help identify suspected abnormalities involving the eighth cranial nerve and related auditory pathways.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abreaction is a psychotherapy process in which a person becomes less sensitive to emotionally painful memories, often ones that have been forgotten or repressed, by bringing them back to mind and expressing their reactions to them in a safe therapeutic setting.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
An absence seizure is a type of generalized seizure marked by a brief period of reduced awareness or impaired consciousness. It may happen with or without movement-related signs such as clonic-tonic activity, automatisms, or autonomic changes.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Absent-mindedness is a state in which attention is so strongly focused on one thought or part of experience that other things in awareness are overlooked. In a more persistent or abnormal form, it involves habitual preoccupation, reduced awareness of surroundings, and difficulty shifting attention from one focus to another.
research methods
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Absolute difference is the distance between two numbers without regard to which one is larger. It is found by taking the absolute value of their difference, so reversing the numbers gives the same result.
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Absolute idealism is a metaphysical view, especially associated here with Hegel, that reality is fully the expression of reason or mind, so that what is real and what is rational ultimately coincide. More broadly, it includes theories that explain the universe and its development as the realization of reason, self-consciousness, or spirit rather than as mere material or mechanical fact.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
An absolute impression is an initial, direct experience taken as it first appears, before the mind has developed a true act of comparing one thing with another. In this usage, it marks an earlier stage in the formation of judgment.
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Absolute reality refers to an ultimate unity in which the knower and what is known are not separate, but form one whole. In this historical usage, it means the total reality that includes the universe and human thought and action, especially as the source of what is most universal and valuable in human experience.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
The absolute refractory period is the brief time after an action potential when a cell membrane is temporarily unable to respond to any new stimulus. During this phase, no stimulus can trigger another response as the membrane returns toward its resting, excitable state.
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Absolutism, in aesthetics, is the view that beauty is objective rather than dependent on the observer, so there can be a fixed standard for judging what is beautiful. In this view, differences in taste reflect differences in people’s ability to recognize or appreciate that objective beauty.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abstinence syndrome is a group of symptoms that can appear after stopping an abused substance. The signs differ by substance and can include irritability, shaking, and vomiting, and the course depends on how well the withdrawal symptoms are managed.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
An abstract idea is a mental grasp of the shared qualities or attributes of something, considered on their own rather than as they appear in many separate examples. It goes beyond a general idea by setting aside the different instances and focusing only on the common character, such as thinking of humanity rather than particular people.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abstract intelligence means reason considered in its pure or general form. In the source, it is linked with the Greek idea of nous and contrasted with logos, which refers to reason as it is expressed or active.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abstraction is the mental process of focusing attention on features of something that matter for a current purpose while recognizing and setting aside features that do not. In thought, it helps a person connect a part or quality of one experience with similar parts or qualities in other experiences, rather than staying with the whole original context.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abulia is a loss or marked lack of the ability to exercise will. It refers to weakened or absent volition and may appear in different forms.
ethics
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abuse is improper use of something or harmful treatment of a person. It refers broadly to actions that are generally understood to cause harm.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Abuse potential is the regulated category used to indicate how likely an active drug ingredient, or a combination of ingredients, is to be misused or abused. In the United States, this classification is assigned under oversight by the DEA and the FDA.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
ACA refers to the anterior cerebral artery, one of two arteries that branch from the internal carotid artery and form part of the Circle of Willis. The left and right anterior cerebral arteries are linked by the anterior communicating artery.
learning
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Academic refers to the college, university, or institute setting associated with study and scholarly life.
learning
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Academic achievement is the extent to which a person engages in meaningful educational activities, gains the intended knowledge and skills, and is satisfied with that progress. It also includes persistence in education and reaching desired educational outcomes.
learning
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Academic failure is a student’s unsuccessful effort to achieve academically, or a clear inadequacy in scholarship or study. It is different from underachievement, which means performing below what would be expected based on measured aptitude or intelligence.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acalculia is a loss or reduction of the ability to do simple mathematical tasks that develops after the skill was previously present.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acamprosate is a substance related in structure to taurine that is used to help prevent relapse in people with alcoholism.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acatamathesia is an inability to understand ordinary conversation, along with dulled perception. In this historical source, it is described as a degenerative sign seen in some chronic forms of insanity.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acataphasia is a speech disorder in which a person can understand and say words, but cannot put them together properly in a sentence. It is an aphasic problem affecting the syntactic, or sentence-order, relationships among words.
development
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acceleration is the historical idea that new traits or changes in a developmental line first appear in later stages of growth and, over generations, come to show up at progressively earlier stages, sometimes even in the embryo. In this sense, it refers to an earlier appearance in development of characteristics that were originally seen later.
cognition
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Accent is a term in phonology for differences in the quality, pitch, or stress of vowel sounds, and it can also refer to the written marks used to show those pronunciation differences. The word is also used more loosely for the characteristic coloring of pronunciation in a person’s or community’s speech.
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
In this historical usage, acceptance was proposed as a better term than recognition for translating the German Anerkennung. It refers to a conceptual or philosophical sense of acknowledging or granting regard, rather than a clinical technique or diagnosis.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acceptance and commitment therapy is a context-focused form of cognitive behavioral psychotherapy. It uses mindfulness and behavioral activation to help people become more psychologically flexible, so they can keep acting in ways that fit their values even when difficult thoughts, feelings, or bodily sensations are present.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
The accessory nerve is the 11th cranial nerve. It arises from neurons in the medulla and cervical spinal cord, with one part joining the vagus nerve to supply motor fibers to the larynx and another part supplying motor fibers to the trapezius and sternocleidomastoid muscles.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Accident proneness is a tendency to be involved in accidents repeatedly. The term suggests that certain personality characteristics may make some people more likely to have accidents.
social
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acculturation is the process in which a person or group takes on traits or social patterns from a different population group.
history
Candidate: drafted from the sources shown, not yet read by the two reviewers.
In historical grammar, the accusative is the case form that complements a verb by marking the direction of its action or the point to which the action applies. It is one of the oblique case relations discussed within systems of declension.
mental health
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acetaldehyde is a colorless, flammable liquid used in making acetic acid, perfumes, and flavorings. In mental health contexts, it is relevant as a substance formed during alcohol metabolism that has general narcotic effects and can irritate mucous membranes; very large amounts can stop breathing and cause death.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acetaminophen is a drug derived from p-aminophenol that reduces pain and fever. Its exact action is not fully known, but it may raise the pain threshold by affecting nitric oxide-related pathways linked to several neurotransmitter receptors, and it may lower fever by reducing prostaglandin activity in the central nervous system.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acetazolamide is a carbonic anhydrase inhibitor that can help reduce some kinds of seizures, including absence seizures, though its benefit may be temporary because tolerance can develop quickly. Its antiseizure action is linked to blocking carbonic anhydrase in the brain, which increases inhibitory nerve signaling.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acetylcholine is a neurotransmitter, a chemical messenger used by nerve cells. It is found where nerves communicate with muscles, in parts of the autonomic nervous system, and in many areas of the central nervous system.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
An acetylcholine receptor is a group of receptor proteins that span the cell membrane, bind the chemical messenger acetylcholine, and start signaling pathways that depend on acetylcholine.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Acetylcholinesterase is an enzyme that breaks down the neurotransmitter acetylcholine into choline and acetate. In the nervous system, it helps support signaling at peripheral neuromuscular junctions.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
An acetylcholinesterase inhibitor is a substance that blocks the enzyme acetylcholinesterase, which normally breaks down acetylcholine in the synaptic cleft. This causes acetylcholine to remain active longer and at higher levels.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
AChE, or acetylcholinesterase, is an enzyme made from the human ACHE gene. It helps break down acetylcholine and is also involved in neuronal apoptosis and in the structure of the Cartwright (Yt) blood group antigen.
development
Candidate: drafted from the sources shown, not yet read by the two reviewers.
Achievement is success in reaching a desired goal or outcome. It can also mean the amount or level of success a person attains in a particular area, especially in school, or more generally.
biological
Candidate: drafted from the sources shown, not yet read by the two reviewers.
AChR refers to acetylcholine receptors, a family of receptor proteins that span cell membranes. They bind acetylcholine and start signaling pathways that depend on this chemical messenger.
development
Candidate: drafted from the sources shown, not yet read by the two reviewers.
ACoA stands for the American College of Oncology Administrators, a US nonprofit professional association for people who manage and administer cancer care services. It supports oncology administrators through education, funding, and peer networking resources.
The dictionary is being built from sources that permit reuse. Definitions include their sources, version and citation. Candidates are published before the two-reader pass and clearly labelled. Reviewed entries have one independent reader; judged entries have two. The drafter does not count; vignettes come later.