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psycho

1 American  
[sahy-koh] / ˈsaɪ koʊ /

noun

plural

psychos
  1. a psychopathic or psychotic person.

  2. a crazy or mentally unstable person.


adjective

  1. psychopathic or psychotic.

  2. crazy; mentally unstable.

psycho- 2 American  
  1. a combining form representing psyche (psychological ) and psychological (psychoanalysis ) in compound words.


psycho- 1 British  

combining form

  1. indicating the mind or psychological or mental processes

    psychology

    psychogenesis

    psychosomatic

"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

psycho 2 British  
/ ˈsaɪkəʊ /

noun

  1. an informal and offensive word for psychopath or psychopathic See psychopath

"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

Usage

What does psycho- mean? Psycho- is a combining form used like a prefix meaning either “psyche” or "psychological." Psyche denotes "the human soul, spirit, or mind," while psychological is a related yet distinct term that means "pertaining to psychology, the science of the mind or of mental states." Psycho- is often used in medical and technical terms, especially in psychology.Psycho- comes from Greek psȳchḗ, meaning “breath, spirit, soul, mind.” For more on the meaning of this word in Ancient Greek mythology, read our entry for psyche. The word psyche is at the root of the term psychedelic, which refers to the effect of hallucinogenic drugs.What are variants of psycho-?When combined with words or word elements that begin with a vowel, psycho- becomes psych-, as in psychiatry. Want to know more? Read our Words That Use article on psych-.

Etymology

Origin of psycho1

First recorded in 1935–40; by shortening

Origin of psycho-2

< Greek, combining form of psȳchḗ breath, spirit, soul, mind; akin to psȳ́chein to blow ( psykter )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"I am just looking at her and thinking she could be sweet but a psycho, like that would be brilliant," Rachel told the other traitors.

From BBC

Gunn’s writing humanized every single character – even Vigilante, a psycho unable to comprehend simple human cues like sarcasm, but who nearly collapses into tears when he realizes he may have failed his friend and hero.

From Salon

The film is part psycho kidnapping horror, part shark thriller and part tribute to Madonna’s “Ray of Light.”

From Salon

“Maybe there’s a part of me that’s a bit of a psycho,” she says of taking up a second project amid the pressing demands of a first.

From Los Angeles Times

After retiring, he didn’t stop feeding into being a basketball sicko — his words — or a full-on basketball psycho — his and his peers’ words.

From Los Angeles Times