| Term | Definition |
| psychological disorder | behavior patterns or mental processes that cause serious personal suffering or interfere with one's ability to cope with daily life |
| maladaptive | interfering with the ability to cope in daily life |
| culture-bound syndrome | a pattern of abnormal behavior recognized in specific cultures that may or may not be linked to an official category of psychological disorder |
| anxiety | a general state of dread or uneasiness that occurs in response to a vague or imagined danger |
| phobia | fear (from the Greek word for fear "phobos") |
| specific phobia (simple phobia) | an anxiety disorder marked by a persistent, irrational fear and avoidance of a specific object or situation |
| social phobia | fear and anxiety of being judged and evaluated by other people |
| panic attack | an episode of intense fear or discomfort accompanied by physical and psychological symptoms such as dizziness, breathing difficulties, chest pain, fear of impending doom, etc. |
| agoraphobia | fear of being in places in which escape may be difficult or impossible |
| obsession | Unwanted thought that a person can't stop thinking about |
| compulsion | Ritualistic behavior that person feels they must do |
| post-traumatic stress disorder | extreme anxiety after event that almost anyone would find stressful |
| mood | long-lasting emotion that affects how one perceives the world |
| depression | feelings of sadness, helplessness, guilt, worthlessness, and hopelessness; the "common cold" of serious mental illness |
| mania | state characterized by excessive elation, irritability, talkativeness, inflated self-esteem, and expansiveness |
| atypical | statistically uncommon |
| socially unacceptable | society's "rules" discourage it |
| DSM-IV-TR | Diagnostic and Statistical Manual of Mental Disorders; used to diagnose mental disorders |
| obsessive-compulsive disorder | disorder that features either obsessions, compulsions, or both |
| major depressive disorder | a mood disorder in which a person, for no apparent reason, experiences two or more weeks of depressed moods, feelings of worthlessness, and diminishes interest or pleasure in most activities |
| delusions | false beliefs, often of persecution or grandeur, that may accompany psychotic disorders |
| schizophrenia | a group of disorders marked by lack of reality testing, and disturbances in thought, perception, language, behavior, and emotions |
| psychotic | inability to reliably determine reality from imaginary |
| paranoid schizophrenia | type of schizophrenia characterized by hallucinations and delusions of persecution or grandeur (or both), and sometimes irrational jealousy. |
| disorganized schizophrenia | type of schizophrenia characterized by disturbed thought and language processes, disorgananized behavior, and inappropriate emotions |
| undifferentiated schizophrenia | mixture of symptoms and does not meet the diagnostic criteria for any one type of schizophrenia |
| bipolar disorder | a mood disorder characterized by episodes of mania and depression |
| personality disorders | Ongoing pattern of inner experience and behavior that differs from cultural expectations |
| seasonal affective disorder | symptoms of major depression during fall and winter |
| hallucinations | false sensory perceptions |
| loose associations | thoughts are unrelated |
| poverty of content | using many words, but conveying little meaning |
| clanging | using words together only because they rhyme or sound similar |
| word salad | language is so jumbled that it makes no sense |
| negative symptoms | an absence of certain normal behaviors |
| catatonic rigidity | abnormal stiffness of the arms and/or legs |
| catatonic posturing | holding an odd position for long periods of time |
| catatonic stupor | symptom of schizophrenia marked by inability to move or react to the environment. |