psycho

1 of 2

noun

psy·​cho ˈsī-(ˌ)kō How to pronounce psycho (audio)
plural psychos
informal + disparaging

psycho

2 of 2

adjective

informal + disparaging
: of, relating to, or being a person who is mentally or emotionally unsound or unstable especially in a way that results in dangerous or violent behavior

Examples of psycho in a Sentence

Noun a story based on a real-life psycho who had serious mother-son issues
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Highly skilled licensed therapists strive to help custodial and visiting parents to better understand and meet the physical and emotional needs of their children through psycho-education, skill building, and processing the impact of family trauma and separation. Patricia Fersch, Forbes.com, 20 Aug. 2025 So that guy was always a little psycho with a taste for violence. Maggie Fremont, Vulture, 9 Aug. 2025
Adjective
The key figure turns out to be Alex’s mysterious Aunt Gladys, played in full psycho-biddy drag by Amy Madigan. Louis Peitzman, Vulture, 8 Aug. 2025 See All Example Sentences for psycho

Word History

Etymology

Noun

short for psychopath

Adjective

short for psychopathic entry 1

First Known Use

Noun

1919, in the meaning defined above

Adjective

1945, in the meaning defined above

Time Traveler
The first known use of psycho was in 1919

Browse Nearby Words

Cite this Entry

“Psycho.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psycho. Accessed 11 Sep. 2025.

Kids Definition

psycho

1 of 2 noun
psy·​cho ˈsī-kō How to pronounce psycho (audio)
informal
: a person of unsound mind
used disparagingly

psycho-

2 of 2 combining form
: mind : mental processes and activities
psychotherapy
Etymology

Noun

short for psychopath

Combining form

derived from Greek psychē "soul, mind, principle of life"

More from Merriam-Webster on psycho

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