noun \ˈsī-(ˌ)kō\

: a person who is mentally ill and often dangerous or violent

plural psychos

Full Definition of PSYCHO

:  a deranged or psychopathic person —not used technically
psycho adjective

Examples of PSYCHO

  1. He plays a drug-dealing psycho in the movie.
  2. <a story based on a real-life psycho who had serious mother-son issues>

Origin of PSYCHO

short for psychopath
First Known Use: 1942

Other Psychology Terms

fetish, hypochondria, intelligence, mania, narcissism, neurosis, pathological, psychosis, schadenfreude, subliminal


noun \ˈsī-(ˌ)kō\   (Medical Dictionary)
plural psychos

Medical Definition of PSYCHO

: a deranged or psychopathic individual—not used technically
psycho adjective


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