Simple Definition of psycho
: a person who is mentally ill and often dangerous or violent
Full Definition of psycho
: a deranged or psychopathic person —not used technically
Examples of psycho
He plays a drug-dealing psycho in the movie.
<a story based on a real-life psycho who had serious mother-son issues>
Origin of psycho
short for psychopath
First Known Use: 1942
Medical Definition of psycho
: a deranged or psychopathic individual—not used technically
Seen and Heard
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