Dictionary.com

psycho

[ sahy-koh ]
/ ˈsaɪ koʊ /
Slang.
SEE SYNONYMS FOR psycho ON THESAURUS.COM

noun, plural psy·chos.

a psychopathic or psychotic person.
a crazy or mentally unstable person.

adjective

psychopathic or psychotic.
crazy; mentally unstable.

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Origin of psycho

First recorded in 1935–40; by shortening

Words nearby psycho

psychic energizer, psychic energy, psychic income, psychic research, psychic trauma, psycho, psychoacoustics, psychoactive, psychoanal., psychoanalyse, psychoanalysis

Definition for psycho (2 of 2)

psycho-

a combining form representing psyche (psychological) and psychological (psychoanalysis) in compound words.
Also especially before a vowel, psych-.

Origin of psycho-

<Greek, combining form of psȳchḗ breath, spirit, soul, mind; akin to psȳ́chein to blow (see psykter)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Words related to psycho

loony, psychotic, crazy, nuts, psychoneurotic, crazed, mad, mental, psychopathic, screwy, unbalanced, certifiable

Example sentences from the Web for psycho

British Dictionary definitions for psycho (1 of 2)

psycho
/ (ˈsaɪkəʊ) /

noun, adjective plural -chos

an informal and offensive word for psychopath or psychopathicSee psychopath

British Dictionary definitions for psycho (2 of 2)

psycho-

sometimes before a vowel psych-

combining form

indicating the mind or psychological or mental processespsychology; psychogenesis; psychosomatic

Word Origin for psycho-

from Greek psukhē spirit, breath
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for psycho (1 of 2)

psycho
[ sī′kō ]

n.

A psychopath.

adj.

Crazy; insane.

Medical definitions for psycho (2 of 2)

psycho-

pref.

Mind; mental:psychogenic.
Mental activities or processes:psychomotor.
Psychology; psychological:psychosocial.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.