Simple Definition of psycho

from our Learner's Dictionary

psycho

noun

ˈsaɪkoʊ How to pronounce psycho (audio)
plural psychos
informal : a person who is mentally ill and often dangerous or violent : psychopath
He plays a drug-dealing psycho in the movie.

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“Psycho.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/psycho. Accessed 21 Jun. 2026.

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