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
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Noun
The message is that men will literally make acoustic concept albums about psycho killers instead of going to therapy. Rob Sheffield, Rolling Stone, 2 Nov. 2025 Spoofing slashers and their tired cliches with a new perspective, the comedy features Alan Tudyk and Tyler Labine as good-natured hillbillies assumed to be backwoods psycho killers by a bunch of college students. Brian Truitt, USA Today, 18 Oct. 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 8 Nov. 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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