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Mental Health and Behavior Glossary

Terms used to explain Mental Health and Behavior can sometimes be confusing. To help you fully understand the articles and features related to this very important health topic, we have compiled a glossary of terms that can help.


Function: abbreviation

1 achievement age
2 Alcoholics Anonymous


Function: abbreviation
attention deficit disorder


Function: abbreviation
attention-deficit/hyperactivity disorder


Function: abbreviation
autonomic nervous system


Pronunciation: \ə-ˈkyüt\

Function: adjective

1: sensing or perceiving accurately, clearly, effectively, or sensitively <acute vision>
2 a: characterized by sharpness or severity <acute pain> <an acute infection>
b (1): having a sudden onset, sharp rise, and short course <an acute disease> <an acute inflammation> compare chronic 2a
(2): see: acute care<an acute hospital>
c: lasting a short time <acute experiments>


Pronunciation: \ə-ˈdik-shən\

Function: noun
: compulsive physiological need for and use of a habit-forming substance (as heroin, nicotine, or alcohol) characterized by tolerance and by well-defined physiological symptoms upon withdrawal; broadly: persistent compulsive use of a substance known by the user to be physically, psychologically, or socially harmful compare habituation

Adrenal Gland

adrenal gland
Function: noun
: either of a pair of complex endocrine organs near the anterior medial border of the kidney consisting of a mesodermal cortex that produces glucocorticoid, mineralocorticoid, and androgenic hormones and an ectodermal medulla that produces epinephrine and norepinephrine —called also adrenal, suprarenal gland


Pronunciation: \ˌag(-ə)-rə-ˈfō-bē-ə\

Function: noun
: abnormal fear of being helpless in a situation from which escape may be difficult or embarrassing that is characterized initially often by panic or anticipatory anxiety and finally by avoidance of open or public places


Pronunciation: \ˌā-ˌgran-yə-lō-ˌsī-ˈtō-səs\

Function: noun

1: an acute febrile condition marked by severe depression of the granulocyte-producing bone marrow and by prostration, chills, swollen neck, and sore throat sometimes with local ulceration and believed to be basically a response to the side effects of certain drugs of the coal-tar series (as aminopyrine) —called also agranulocytic angina, granulocytopenia

Anorexia Nervosa

anorexia ner*vo*sa
Pronunciation: \-(ˌ)nər-ˈvō-sə, -zə\

Function: noun
: a serious eating disorder primarily of young women in their teens and early twenties that is characterized esp. by a pathological fear of weight gain leading to faulty eating patterns, malnutrition, and usu. excessive weight loss


Function: noun
: an antidepressant drug —called also energizer, psychic energizer, psychostimulant, compare tricyclic antidepressant


Function: noun
: any of various compounds that oppose the actions of histamine and are used esp. for treating allergic reactions (as hay fever), cold symptoms, and motion sickness


Pronunciation: \aŋ-ˈzī-ət-ē\

Function: noun
pl -eties

1 a: a painful or apprehensive uneasiness of mind usu. over an impending or anticipated ill
b: a cause of anxiety
2: an abnormal and overwhelming sense of apprehension and fear often marked by physiological signs (as sweating, tension, and increased pulse), by doubt concerning the reality and nature of the threat, and by self-doubt about one's capacity to cope with it

Anxiety Disorder

Function: noun
: any of various disorders (as panic disorder, obsessive-compulsive disorder, a phobia, or generalized anxiety disorder) in which anxiety is a predominant feature —called also anxiety neurosis, anxiety state


Pronunciation: \(ˈ)ā-ˈprak-sē-ə\

Function: noun
: loss or impairment of the ability to execute complex coordinated movements without muscular or sensory impairment compare eupraxia


Pronunciation: \är-ˌtir-ē-ō-sklə-ˈrō-səs\

Function: noun
pl -ro*ses
Pronunciation: \-ˌsēz\
: a chronic disease characterized by abnormal thickening and hardening of the arterial walls with resulting loss of elasticity compare atherosclerosis


Pronunciation: \ə-ˈten-chən\

Function: noun

1: the act or state of attending : the application of the mind to any object of sense or thought
2 a: an organismic condition of selective awareness or perceptual receptivity; specif: the complex of neuromuscular adjustments that permit maximum excitability or responsiveness to a given class of stimuli
b: the process of focusing consciousness to produce greater vividness and clarity of certain of its contents relative to others


Pronunciation: \ˌod-ē-ˈäl-ə-jəst\

Function: noun
: a specialist in audiology


Pronunciation: \ˈo-ˌtiz-əm\

Function: noun

1: a developmental disorder that appears by age three and that is variable in expression but is recognized and diagnosed by impairment of the ability to form normal social relationships, by impairment of the ability to communicate with others, and by stereotyped behavior patterns esp. as exhibited by a preoccupation with repetitive activities of restricted focus rather than with flexible and imaginative ones


Function: abbreviation
benign prostatic hyperplasia; benign prostatic hypertrophy


Pronunciation: \-ˈbläk-ər\

Function: noun
: any of a group of drugs (as propranolol) that combine with and block the activity of a beta-receptor to decrease the heart rate and force of contractions and lower high blood pressure and that are used esp. to treat hypertension, angina pectoris, and ventricular and supraventricular arrhythmias compare alpha-blocker

Bipolar Disorder

Function: noun
: any of several mood disorders characterized usu. by alternating episodes of depression and mania or by episodes of depression alternating with mild nonpsychotic excitement —called also bipolar affective disorder, bipolar illness, manic depression, manic-depressive psychosis, compare major depressive disorder


Pronunciation: \brän-ˈkīt-əs, bräŋ-\
Function: noun
1: acute or chronic inflammation of the bronchial tubes; also: a disease marked by this

CT Scan

CT scan
Pronunciation: \(ˈ)sē-ˈtē-\

Function: noun
: see: cat scan

Carbon Monoxide

carbon monoxide
Function: noun
: a colorless odorless very toxic gas CO that burns to carbon dioxide with a blue flame and is formed as a product of the incomplete combustion of carbon


Pronunciation: \ˈkat-ə-ˌrakt\

Function: noun
: a clouding of the lens of the eye or its surrounding transparent membrane that obstructs the passage of light


Pronunciation: \sə-ˈrē-brəl, ˈser-ə-\

Function: adjective

1: of or relating to the brain or the intellect
2: of, relating to, affecting, or being the cerebrum <cerebral blood flow> <cerebral toxoplasmosis>

Chemical Dependence

chemical dependence
Function: noun
: addiction to or dependence on drugs


Pronunciation: \ˈkrän-ik\

Function: adjective

1 a: marked by long duration, by frequent recurrence over a long time, and often by slowly progressing seriousness : not acute <chronic[1] indigestion> <her hallucinations became chronic[1]>
b: suffering from a disease or ailment of long duration or frequent recurrence <a chronic[1] arthritic> <chronic[1] sufferers from asthma>
2 a: having a slow progressive course of indefinite duration used esp. of degenerative invasive diseases, some infections, psychoses, and inflammations <chronic[1] heart disease> <chronic[1] arthritis> <chronic[1] tuberculosis> compare acute 2b(1)
b: infected with a disease-causing agent (as a virus) and remaining infectious over a long period of time but not necessarily expressing symptoms <chronic[1] carriers may remain healthy but still transmit the virus causing hepatitis B>


Pronunciation: \sə-ˈrō-səs\

Function: noun
pl -rho*ses
Pronunciation: \-ˌsēz\

: widespread disruption of normal liver structure by fibrosis and the formation of regenerative nodules that is caused by any of various chronic progressive conditions affecting the liver (as long-term alcohol abuse or hepatitis) see biliary cirrhosis

Cognitive Behavioral Therapy

Function: noun
1: see: cognitive therapy


Pronunciation: \ˌsī-klə-ˈthī-mē-ə\

Function: noun
: a cyclothymic mood disorder


Pronunciation: \di-ˈlir-ē-əm\

Function: noun
: a mental disturbance characterized by confusion, disordered speech, and hallucinations


Pronunciation: \di-ˈlü-zhən\

Function: noun

1. a: the act of deluding : the state of being deluded
b: an abnormal mental state characterized by the occurrence of psychotic delusions
2: a false belief regarding the self or persons or objects outside the self that persists despite the facts and occurs in some psychotic states compare hallucination 1 illusion 2a


Pronunciation: \di-ˈnī(-ə)l\

Function: noun
: a psychological defense mechanism in which confrontation with a personal problem or with reality is avoided by denying the existence of the problem or reality


Pronunciation: \-ənt\

Function: adjective
: tending to depress; esp: lowering or tending to lower functional or vital activity <a drug with a depressant[1] effect on heart rate>


Pronunciation: \di-ˈpresh-ən\

Function: noun

1: a displacement downward or inward <depression of the jaw>
2: an act of depressing or a state of being depressed: as
a (1): a state of feeling sad
(2): a psychoneurotic or psychotic disorder marked esp. by sadness, inactivity, difficulty with thinking and concentration, a significant increase or decrease in appetite and time spent sleeping, feelings of dejection and hopelessness, and sometimes suicidal thoughts or an attempt to commit suicide
b: a reduction in functional activity, amount, quality, or force <depression of autonomic function> <depression of red blood cells>


Pronunciation: \(ˈ)dē-ˈtäks\

Function: noun

1often attrib: detoxification from an intoxicating or addictive substance <began performing ultra rapid detox[1]esCarol Ann Campbell & Fredrick Kunkle> <a detox[1] program> <a detox[1] clinic>
2: a detox program or facility <spent five days in detox[1] at a local hospital Karl Ross>


Pronunciation: \ˌdē-t(y)ü-ˈmes-ən(t)s\

Function: noun
: subsidence or diminution of swelling or erection


Pronunciation: \ˈdek-sə-ˌdrēn, -drən\

Function: trademark
used for a preparation of the sulfate of dextroamphetamine


Function: noun
: abnormally frequent intestinal evacuations with more or less fluid stools


Function: noun
: psychopathological inconsistency in personality, mental functions, or overt behavior <psychotic disorganization> <psychomotor disorganization>


Pronunciation: \ˈdō-pə-ˌmēn\

Function: noun
1: a monoamine C8H11NO2 that is a decarboxylated form of dopa and occurs esp. as a neurotransmitter in the brain and as an intermediate in the biosynthesis of epinephrine see intropin


Pronunciation: \dis-ˈlek-sē-ə\

Function: noun
: a variable often familial learning disability involving difficulties in acquiring and processing language that is typically manifested by a lack of proficiency in reading, spelling, and writing


Pronunciation: \dis-ˈprak-sē-ə, -ˈprak-sh(ē-)ə\

Function: noun
: impairment of the ability to perform coordinated movements <dyspraxias of gaze A. G. Waltz>


Function: abbreviation
electroencephalogram; electroencephalograph


Pronunciation: \ˌek-ō-ˈlā-lē-ə\

Function: noun
: the often pathological repetition of what is said by other people as if echoing them


Pronunciation: \i-ˈlā-shən\

Function: noun
: pathological euphoria sometimes accompanied by intense pleasure

Electroconvulsive Therapy

electroconvulsive therapy
Function: noun
: the treatment of mental disorder and esp. depression by the application of electric current to the head of a usu. anesthetized patient that induces unconsciousness and convulsive seizures in the brain abbr. ECT—called also electric shock, electric shock therapy, electroshock therapy


Pronunciation: \ˌem(p)-fə-ˈzē-mə, -ˈsē-\
Function: noun
1: a condition characterized by air-filled expansions in interstitial or subcutaneous tissues; specif: a condition of the lung that is marked by distension and eventual rupture of the alveoli with progressive loss of pulmonary elasticity, that is accompanied by shortness of breath with or without cough, and that may lead to impairment of heart action


Pronunciation: \ˈep-ə-ˌlep-sē\

Function: noun
pl -sies
: any of various disorders marked by abnormal electrical discharges in the brain and typically manifested by sudden brief episodes of altered or diminished consciousness, involuntary movements, or convulsions see grand mal petit mal focal epilepsy jacksonian epilepsy myoclonic epilepsy temporal lobe epilepsy


Function: noun
: a colorless crystalline feebly basic sympathomimetic hormone C9H13NO3 that is the principal blood-pressure-raising hormone secreted by the adrenal medulla, is prepared from adrenal extracts or made synthetically, and is used medicinally esp. as a heart stimulant, as a vasoconstrictor (as to treat open-angle glaucoma and life-threatening allergic reactions and to prolong the effects of local anesthetics), and as a bronchodilator —called also adrenaline


Pronunciation: \i-ˈrek-shən\

Function: noun

1: the state marked by firm turgid form and erect position of a previously flaccid bodily part containing cavernous tissue when that tissue becomes dilated with blood
2: an occurrence of erection in the penis or clitoris


Pronunciation: \ˈeth-ə-ˌnol, -ˌnōl\

Function: noun
: a colorless volatile flammable liquid C2H5OH that is the intoxicating agent in liquors and is also used as a solvent —called also ethyl alcohol, grain alcohol, see alcohol 1


Pronunciation: \yu-ˈfōr-ē-ə, -ˈfor-\

Function: noun
1: a feeling of well-being or elation; esp: one that is groundless, disproportionate to its cause, or inappropriate to one's life situation compare dysphoria


Pronunciation: \ik-ˈsīt-ə-ˌtäk-sən\

Function: noun
: an excitotoxic agent (as kainic acid)


Function: abbreviation
Food and Drug Administration


Pronunciation: \(ˌ)fər-ˈtil-ət-ē\

Function: noun
pl -ties

1: the quality or state of being fertile
2: the birthrate of a population compare mortality 2b

Fetal Alcohol Syndrome

fetal alcohol syndrome
Function: noun
: a highly variable group of birth defects including mental retardation, deficient growth, central nervous system dysfunction, and malformations of the skull and face that tend to occur in the offspring of women who consume large amounts of alcohol during pregnancy abbr. FAS


Pronunciation: \ˈflas-əd, ˈflak-səd\

Function: adjective
: not firm or stiff; also: lacking normal or youthful firmness <flaccid muscles>


Function: verb
also fo*cussed
also fo*cus*sing
transitive verb
1: to bring (as light rays) to a focus
2 a: to adjust the focus of (as the eye or a lens)
b: to bring (as an image) into focusintransitive verb
1: to come to a focus
2: to adjust one's eye or a camera to a particular range

Fragile X Syndrome

fragile X syndrome
Pronunciation: \-ˈeks-\

Function: noun
: an X-linked inherited disorder that is caused by repeats of a trinucleotide sequence on the X chromosome which are abnormal in number and degree of methylation, that is characterized by moderate to severe mental retardation, by large ears, chin, and forehead, and by enlarged testes in males, and that often has limited or no effect in heterozygous females —called also fragile X


Pronunciation: \ˌgas-trō-in-ˈtes-tən-əl, -ˈtes(t)-nəl\

Function: adjective
: of, relating to, or affecting both stomach and intestine <gastrointestinal distress>


Pronunciation: \jə-ˈnet-ik\

Function: adjective

1: of, relating to, or involving genetics
2: of, relating to, caused by, or controlled by genes <a genetic disease> <genetic material> compare acquired 1


Pronunciation: \ˌjin-jə-ˈvīt-əs\

Function: noun
: inflammation of the gums


Pronunciation: \ˈglüt-ə-ˌmāt\

Function: noun
: a salt or ester of glutamic acid; specif: a salt or ester of levorotatory glutamic acid that functions as an excitatory neurotransmitter see monosodium glutamate


Pronunciation: \hə-ˌlüs-ən-ˈā-shən\

Function: noun

1: a perception of something (as a visual image or a sound) with no external cause usu. 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 (as LSD) compare delusion 2 illusion 2a
2: the object of a hallucinatory perception


Pronunciation: \-ˌō-vər\

Function: noun
: disagreeable physical effects (as headache or nausea) following heavy consumption of alcohol or the use of drugs


Pronunciation: \ˈhed-ˌāk\

Function: noun
: pain in the head —called also cephalalgia

Heart Attack

heart attack
Function: noun
: an acute episode of heart disease marked by the death or damage of heart muscle due to insufficient blood supply to the heart muscle usu. as a result of a coronary thrombosis or a coronary occlusion and that is characterized esp. by chest pain —called also myocardial infarction, compare angina pectoris coronary insufficiency heart failure 1

Heart Disease

Function: noun
1: an abnormal organic condition of the heart or of the heart and circulation

Heart Rate

heart rate
Function: noun
: a measure of cardiac activity usu. expressed as number of beats per minute see maximum heart rate


Pronunciation: \ˌhip-ə-ˈkam-pəs\

Function: noun
pl -pi
Pronunciation: \-ˌpī, -(ˌ)pē\
: a curved elongated ridge that is an important part of the limbic system, extends over the floor of the descending horn of each lateral ventricle of the brain, consists of gray matter covered on the ventricular surface with white matter, and is involved in forming, storing, and processing memory see pes hippocampi


Pronunciation: \ˌhī-pə-ˈrak-tiv\

Function: adjective
: affected with or exhibiting hyperactivity; broadly: more active than is usual or desirable


Pronunciation: \ˌhī-pə-ˌrak-ˈtiv-ət-ē\

Function: noun
pl -ties
: a state or condition of being excessively or pathologically active; esp: see: attention deficit disorder


Pronunciation: \hip-ˈnō-səs\

Function: noun
pl -no*ses
Pronunciation: \-ˌsēz\

1: a trancelike state of altered consciousness that resembles sleep but is induced by a person whose suggestions are readily accepted by the subject
2: any of various conditions that resemble sleep
3: see: hypnotism 1


Pronunciation: \ˌhī-pə-ˈmā-nē-ə, -nyə\

Function: noun
: a mild mania esp. when part of bipolar disorder


Pronunciation: \-ˈthal-ə-məs\

Function: noun
pl -mi
Pronunciation: \-ˌmī\
: a basal part of the diencephalon that lies beneath the thalamus on each side, forms the floor of the third ventricle, and includes vital autonomic regulatory centers (as for the control of food intake)


Pronunciation: \il-ˈü-zhən\

Function: noun

1: a misleading image presented as a visual stimulus
2. a: perception of something objectively existing in such a way as to cause misinterpretation of its actual nature; esp: see: optical illusioncompare delusion 2
b: see: hallucination 1
c: a pattern capable of reversible perspective

Immune System

immune system
Function: noun
: the bodily system that protects the body from foreign substances, cells, and tissues by producing the immune response and that includes esp. the thymus, spleen, lymph nodes, special deposits of lymphoid tissue (as in the gastrointestinal tract and bone marrow), lymphocytes including the B cells and T cells, and antibodies


Pronunciation: \ˈim-pət-ən(t)s\

Function: noun

1: the quality or state of not being potent <drug-resistant bacteria are a virulent indicator of the growing impotence of antibiotics>
2: an abnormal physical or psychological state of a male characterized by inability to copulate because of failure to have or maintain an erection —called also erectile dysfunction


Pronunciation: \ˈin(t)-səd-ən(t)s, -sə-ˌden(t)s\

Function: noun

1 a: see: angle of incidence
b: the arrival of something (as a ray of light) at a surface
2 a: an act or the fact or manner of occurring or affecting <diseases of domestic incidenceScience>
b: rate of occurrence or influence; esp: the rate of occurrence of new cases of a particular disease in a population being studied compare prevalence


Pronunciation: \ˌin-də-ˈkā-shən\

Function: noun

1 a: a symptom or particular circumstance that indicates the advisability or necessity of a specific medical treatment or procedure <postpartum hemorrhage is the chief indication for the use of ergot preparations and derivatives C. H. Thienes>
b: something that is indicated as advisable or necessary <in case of collapse the immediate indication is artificial respiration Jour. Amer. Med. Assoc.>
2: the degree indicated in a specific instance or at a specific time on a graduated physical instrument (as a thermometer)


Pronunciation: \in-ˈsäm-nē-ə\

Function: noun
: prolonged and usu. abnormal inability to obtain adequate sleep —called also agrypnia


Pronunciation: \ˌint-ər-ˈven-chən\

Function: noun
: the act or fact or a method of interfering with the outcome or course esp. of a condition or process (as to prevent harm or improve functioning) <relieving a variety of serious arrhythmias by surgical intervention G. M. Lawrie et al> <develop interventions to prevent substance abuse A. Kline et al>


Pronunciation: \in-ˌtäk-sə-ˈkā-shən\

Function: noun

1: an abnormal state that is essentially a poisoning <hypokalemia potentiates digoxin intoxication W. H. Abelmann et al> <no evidence of cocaine intoxication Margaret M. McCarron et al> <acute carbon monoxide intoxication>
2: the condition of being drunk : see: inebriation

Learning Disability

learning disability
Function: noun
: any of various disorders (as dyslexia or dysgraphia) that interfere with an individual's ability to learn resulting in impaired functioning in verbal language, reasoning, or academic skills (as reading, writing, and mathematics) and are thought to be caused by difficulties in processing and integrating information


Pronunciation: \lə-ˈbēd-(ˌ)ō also ˈlib-ə-ˌdō or lə-ˈbī-(ˌ)dō\

Function: noun
pl -dos

1: instinctual psychic energy that in psychoanalytic theory is derived from primitive biological urges (as for sexual pleasure or self-preservation) and that is expressed in conscious activity
2: sexual drive

Limbic System

limbic system
Function: noun
: a group of subcortical structures (as the hypothalamus, the hippocampus, and the amygdala) of the brain that are concerned esp. with emotion and motivation


Pronunciation: \ˈlith-ē-əm\

Function: noun

1: a soft silver-white element of the alkali metal group that is the lightest metal known and that is used in chemical synthesis and in storage batteries symbol Lisee element table
2: a lithium salt and esp. lithium carbonate used in psychiatric medicine


Pronunciation: \ˌem-(ˌ)är-ˈī\

Function: noun
: see: magnetic resonance imaging; also: a procedure in which magnetic resonance imaging is used

Macular Degeneration

macular degeneration
Function: noun
: progressive deterioration of the macula lutea resulting in a gradual loss of the central part of the field of vision; esp: see: age-related macular degeneration


Pronunciation: \ˈmā-nē-ə, -nyə\

Function: noun
: excitement of psychotic proportions manifested by mental and physical hyperactivity, disorganization of behavior, and elevation of mood; specif: the manic phase of bipolar disorder

Manic Depression

manic depression
Function: noun
: see: bipolar disorder


Pronunciation: \ˌmed-ə-ˈkā-shən\

Function: noun

1: the act or process of medicating
2: a medicinal substance : see: medicament


Pronunciation: \ˈmeth-ə-ˌdōn\

Function: noun
: a synthetic addictive narcotic drug used esp. in the form of its hydrochloride C21H27NO·HCl for the relief of pain and as a substitute narcotic in the treatment of heroin addiction —called also amidone


Pronunciation: \när-ˈkät-ik\

Function: noun

1: a drug (as codeine, methadone, or morphine) that in moderate doses dulls the senses, relieves pain, and induces profound sleep but in excessive doses causes stupor, coma, or convulsions
2: a drug (as marijuana or LSD) subject to restriction similar to that of addictive narcotics whether in fact physiologically addictive and narcotic or not


Pronunciation: \ˈno-zē-ə, -sē-ə; ˈno-zhə, -shə\

Function: noun
: a stomach distress with distaste for food and an urge to vomit


Pronunciation: \-ˈläj-i-kəl\

Function: adjective
: of or relating to neurology


Pronunciation: \ˌn(y)ur-ō-ˌfiz-ē-ˈäl-ə-jē\

Function: noun
1: physiology of the nervous system


Pronunciation: \ˌn(y)ur-ō-tran(t)s-ˈmit-ər, -tranz-\

Function: noun
: a substance (as norepinephrine or acetylcholine) that transmits nerve impulses across a synapse see false neurotransmitter


Pronunciation: \ˈnik-ə-ˌtēn\

Function: noun
: a poisonous alkaloid C10H14N2 that is the chief active principle of tobacco and that is used as an insecticide

Nitric Oxide

nitric oxide
Function: noun
: a poisonous colorless gas NO that occurs as a common air pollutant formed by the oxidation of atmospheric nitrogen and that is also formed by the oxidation of arginine in the mammalian body where it acts as a mediator of intracellular and intercellular communication regulating numerous biological processes (as vasodilation and neurotransmission)


Function: abbreviation
obsessive-compulsive disorder

Obsessive-Compulsive Disorder

obsessive–compulsive disorder
Function: noun
: a psychoneurotic disorder in which the patient is beset with obsessions or compulsions or both and suffers extreme anxiety or depression through failure to think the obsessive thoughts or perform the compelling acts abbr. OCD—called also obsessive-compulsive neurosis, obsessive-compulsive reaction


Pronunciation: \ˈon-ˌset, ˈän-\

Function: noun
: the initial existence or symptoms of a disease <the onset of scarlet fever>


Pronunciation: \ˈor-ˌgaz-əm\

Function: noun
: the climax of sexual excitement that is usu. accompanied by ejaculation of semen in the male and by vaginal contractions in the female


Pronunciation: \ˈaut-ˌlet, -lət\

Function: noun

1: an opening or a place through which something is let out <the pelvic outlet>
2: a means of release or satisfaction for an emotion or impulse <counseling provides an outlet for expressing and evaluating their feelings Vicki Glaser>


Pronunciation: \ˈō-vər-ˌdōs\

Function: noun
: too great a dose (as of a therapeutic agent) <an overdose[1] of exposure to the sun Morris Fishbein> ; also: a lethal or toxic amount (as of a drug)


Function: abbreviation
post-traumatic stress disorder

Panic Attack

panic attack
Function: noun
: an episode of intense fear or apprehension that is of sudden onset and may occur for no apparent reason or as a reaction to an identifiable triggering stimulus (as a stressful event); specif: one that is accompanied by usu. four or more bodily or cognitive symptoms (as heart palpitations, dizziness, shortness of breath, or feelings of unreality) and that typically peaks within 10 minutes of onset

Panic Disorder

Function: noun
: an anxiety disorder characterized by recurrent unexpected panic attacks followed by a month or more of worry about their recurrence, implications, or consequences or by a change in behavior related to the panic attacks


Pronunciation: \ˌpar-ə-ˈnoi-ə\

Function: noun

1: a psychosis characterized by systematized delusions of persecution or grandeur usu. without hallucinations
2: a tendency on the part of an individual or group toward excessive or irrational suspiciousness and distrustfulness of others


Pronunciation: \ˈpar-ə-ˌnoid\

Function: adjective

1: characterized by or resembling paranoia or paranoid schizophrenia
2: characterized by suspiciousness, persecutory trends, or megalomania


Pronunciation: \-jē\

Function: noun
pl -gies

1: the study of the essential nature of diseases and esp. of the structural and functional changes produced by them
2: the anatomic and physiological deviations from the normal that constitute disease or characterize a particular disease
3: a treatise on or compilation of abnormalities <a new pathology of the eye>


Function: noun
pl -nea
also -naea
Pronunciation: \-ˈnē-ə\

: an area of tissue that marks externally the approximate boundary of the pelvic outlet and gives passage to the urogenital ducts and rectum; also: the area between the anus and the posterior part of the external genitalia esp. in the female

Personality Disorder

personality disorder
Function: noun
: a psychopathological condition or group of conditions in which an individual's entire life pattern is considered deviant or nonadaptive although the individual shows neither neurotic symptoms nor psychotic disorganization

Peyronie's Disease

Pey*ro*nie's disease
Pronunciation: \ˌpā-rə-ˈnēz-, pā-ˈrō-(ˌ)nēz-\

Function: noun
: the formation of fibrous plaques in one or both corpora cavernosa of the penis resulting in distortion or deflection of the erect organ


Pronunciation: \ˈfō-bē-ə\

Function: noun
: an exaggerated and often disabling fear usu. inexplicable to the subject and having sometimes a logical but usu. an illogical or symbolic object, class of objects, or situation compare compulsion obsession


Pronunciation: \-ˈther-ə-pē\

Function: noun
pl -pies
: the application of light for therapeutic purposes


Pronunciation: \plə-ˈsē-(ˌ)bō\

Function: noun
pl -bos

1: a usu. pharmacologically inert preparation prescribed more for the mental relief of the patient than for its actual effect on a disorder
2: an inert or innocuous substance used esp. in controlled experiments testing the efficacy of another substance (as a drug)


Function: noun

1 a: a localized abnormal patch on a body part or surface and esp. on the skin <psoriatic plaque>
b: a sticky usu. colorless film on teeth that is formed by and harbors bacteria
c: an atherosclerotic lesion
d: a histopathologic lesion of brain tissue that is characteristic of Alzheimer's disease and consists of a dense proteinaceous core composed primarily of beta-amyloid that is often surrounded and infiltrated by a cluster of degenerating axons and dendrites —called also senile plaque
2: a visibly distinct and esp. a clear or opaque area in a bacterial culture produced by damage to or destruction of cells by a virus


Pronunciation: \n(y)u-ˈmō-nyə\
Function: noun
1: a disease of the lungs that is characterized esp. by inflammation and consolidation of lung tissue followed by resolution, is accompanied by fever, chills, cough, and difficulty in breathing, and is caused chiefly by infection see bronchopneumonia lobar pneumonia primary atypical pneumonia


Pronunciation: \ˌpäl-i-ˈjēn-ik, -ˈjen-ik\

Function: adjective
1: of, relating to, or resulting from polygenes : see: multifactorial<a polygenic disorder>

Post-traumatic Stress Disorder

post–traumatic stress disorder
Function: noun
: a psychological reaction that occurs after experiencing a highly stressing event (as wartime combat, physical violence, or a natural disaster) outside the range of normal human experience and that is usu. characterized by depression, anxiety, flashbacks, recurrent nightmares, and avoidance of reminders of the event abbr. PTSD—called also delayed-stress disorder, delayed-stress syndrome, post-traumatic stress syndrome, compare combat fatigue


Pronunciation: \ˈpreg-nən-sē\

Function: noun
pl -cies

1: the condition of being pregnant
2: an instance of being pregnant

Prescription Drug

prescription drug
Function: noun
: a drug that can be obtained only by means of a physician's prescription


Pronunciation: \ˈprī-ə-ˌpiz-əm\

Function: noun
: an abnormal, more or less persistent, and often painful erection of the penis; esp: one caused by disease rather than sexual desire


Function: adjective
: of, relating to, or being the prostate gland


Pronunciation: \ˌsī-kē-ˈa-trik\

Function: adjective

1: relating to or employed in psychiatry <psychiatric disorders> <psychiatric drugs>
2: engaged in the practice of psychiatry : dealing with cases of mental disorder <psychiatric experts> <psychiatric nursing> <a psychiatric ward>


Pronunciation: \sə-ˈkī-ə-trəst, sī-\

Function: noun
: a physician specializing in psychiatry


Pronunciation: \-jē\

Function: noun
pl -gies

1: the science of mind and behavior
2 a: the mental or behavioral characteristics typical of an individual or group or a particular form of behavior <mob psychology> <the psychology of arson>
b: the study of mind and behavior in relation to a particular field of knowledge or activity <color psychology> <the psychology of learning>
3: a treatise on or a school, system, or branch of psychology


Pronunciation: \sī-ˈkō-səs\

Function: noun

1: a serious mental disorder (as schizophrenia) characterized by defective or lost contact with reality often with hallucinations or delusions


Pronunciation: \ˌsī-kō-ˈther-ə-pē\

Function: noun
pl -pies

1: treatment of mental or emotional disorder or maladjustment by psychological means esp. involving verbal communication (as in psychoanalysis, nondirective psychotherapy, reeducation, or hypnosis)
2: any alteration in an individual's interpersonal environment, relationships, or life situation brought about esp. by a qualified therapist and intended to have the effect of alleviating symptoms of mental or emotional disturbance


Pronunciation: \ˈrānj\

Function: noun
often attrib
1: the region throughout which a kind of organism or ecological community naturally lives or occurs
2: the difference between the least and greatest values of an attribute or of the variable of a frequency distribution


Pronunciation: \ri-ˈlaps, ˈrē-ˌ\

Function: noun
: a recurrence of illness; esp: a recurrence of symptoms of a disease after a period of improvement <a relapse[1] after an 18-month remission M. T. Fosburg et al> compare recrudescence


Pronunciation: \ri-ˈmish-ən\

Function: noun
: a state or period during which the symptoms of a disease are abated <cancer in remission after treatment> compare arrest cure 1 intermission


Pronunciation: \ˈrit-ə-lən\

Function: trademark
used for a preparation of the hydrochloride of methylphenidate


Pronunciation: \ˌskit-sə-ˈfrē-nē-ə\

Function: noun
: a psychotic disorder characterized by loss of contact with the environment, by noticeable deterioration in the level of functioning in everyday life, and by disintegration of personality expressed as disorder of feeling, thought (as in delusions), perception (as in hallucinations), and behavior —called also dementia praecox, see paranoid schizophrenia


Pronunciation: \ˈskrōt-əm\

Function: noun
pl scro*ta
Pronunciation: \-ə\>
or scrotums
: the external sac that in most mammals contains the testes

Seasonal Affective Disorder

sea*son*al affective disorder
Pronunciation: \ˌsēz-ən-əl-\

Function: noun
: depression that tends to recur as the days grow shorter during the fall and winter abbr. SAD


Pronunciation: \ˈsed-ət-iv\

Function: adjective
: tending to calm, moderate, or tranquilize nervousness or excitement <sedative[1] effects of anesthetics and analgesics Linda C. Haynes et al>


Pronunciation: \ˈsē-mən\

Function: noun
: a viscid whitish fluid of the male reproductive tract consisting of spermatozoa suspended in secretions of accessory glands (as of the prostate and Cowper's glands)


Pronunciation: \ˈsen(t)s-(ə-)rē\

Function: adjective

1: of or relating to sensation or the senses <sensory stimulation> <sensory data>
2: conveying nerve impulses from the sense organs to the nerve centers : see: afferent<sensory nerve fibers>


Pronunciation: \ˌsir-ə-ˈtō-nən, ˌser-\

Function: noun
: a phenolic amine neurotransmitter C10H12N2O that is a powerful vasoconstrictor and is found esp. in the brain, blood serum, and gastric mucous membrane of mammals —called also 5-HT, 5-hydroxytryptamine

Side Effect

side effect
Function: noun
: a secondary and usu. adverse effect (as of a drug) <toxic side effects> <a side effect of drowsiness caused by antihistamines> —called also side reaction


Pronunciation: \ˈsti(ə)r-ˌoid also ˈste(ə)r-\

Function: noun
: any of numerous natural or synthetic compounds containing a 17-carbon 4-ring system and including the sterols and various hormones and glycosides see anabolic steroid


Pronunciation: \ˈstres\

Function: noun

1 a: a force exerted when one body or body part presses on, pulls on, pushes against, or tends to compress or twist another body or body part; esp: the intensity of this mutual force commonly expressed in pounds per square inch
b: the deformation caused in a body by such a force
2 a: a physical, chemical, or emotional factor that causes bodily or mental tension and may be a factor in disease causation
b: a state of bodily or mental tension resulting from factors that tend to alter an existent equilibrium
3: the force exerted between teeth of the upper and lower jaws during mastication


Pronunciation: \ˈstrōk\

Function: noun
1: sudden diminution or loss of consciousness, sensation, and voluntary motion caused by rupture or obstruction (as by a clot) of a blood vessel of the brain —called also apoplexy, brain attack, cerebral accident, cerebrovascular accident


Pronunciation: \ˈsin-ˌaps also sə-ˈnaps, chiefly Brit ˈsī-ˌnaps\

Function: noun

1: the place at which a nervous impulse passes from one neuron to another
2: see: synapsis

Tardive Dyskinesia
Function: noun
: a neurological disorder characterized by involuntary uncontrollable movements esp. of the mouth, tongue, trunk, and limbs and occurring esp. as a side effect of prolonged use of antipsychotic drugs (as phenothiazine) abbr. TD


Pronunciation: \ˈtem-pə(r)-ˌchu(ə)r, -p(ə-)rə-, -chər, -ˌt(y)u(ə)r\

Function: noun

1: degree of hotness or coldness measured on a definite scale see thermometer
2 a: the degree of heat that is natural to a living body <a normal oral temperature of about 98.6°F>
b: a condition of abnormally high body heat <was running a temperature>


Pronunciation: \te-ˈstäs-tə-ˌrōn\

Function: noun
: a male hormone that is a crystalline hydroxy steroid ketone C19H28O2 produced primarily by the testes or made synthetically and that is the main androgen responsible for inducing and maintaining male secondary sex characteristics


Pronunciation: \ˈther-ə-pəst\

Function: noun
: a person specializing in therapy; esp: one trained in methods of treatment and rehabilitation other than the use of drugs or surgery


Pronunciation: \ˈther-ə-pē\

Function: noun
pl -pies
: therapeutic treatment: as
a: remedial treatment of mental or bodily disorder
b: an agency (as treatment) designed or serving to bring about rehabilitation or social adjustment see occupational therapy recreational therapy


Pronunciation: \ˈthī-ˌroid\

Function: adjective

1 a: of, relating to, affecting, or being the thyroid gland <thyroid[1] disorders>
2: of, relating to, or being the thyroid cartilage


Pronunciation: \täk-ˈsis-ət-ē\

Function: noun
pl -ties
: the quality, state, or relative degree of being toxic or poisonous


Pronunciation: \yu-ˈrē-thrə\
Function: noun
1: the canal that in most mammals carries off the urine from the bladder and in the male serves also as a passageway for semen


Pronunciation: \ˈvas-kyə-lər\

Function: adjective

1: of, relating to, constituting, or affecting a tube or a system of tubes for the conveyance of a body fluid (as blood or lymph) <vascular disease> <vascular surgical techniques>
2: supplied with or containing ducts and esp. blood vessels <a vascular tumor> <the vascular layer of the skin>


Pronunciation: \-ˈdro(ə-)l\

Function: noun

1 a: a pathological retreat from objective reality (as in some schizophrenic states)
b: social or emotional detachment
2 a: the discontinuance of administration or use of a drug
b: the syndrome of often painful physical and psychological symptoms that follows discontinuance of an addicting substance <a heroin addict going through withdrawal>
3: see: coitus interruptus

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