Definition of psycho in English:

psycho

noun

informal
  • A psychopath.

    • ‘The speech was basically: men are psychos, Americans are psychos, the Americans want to exterminate the planet, and naked protest will end the nuclear age.’
    • ‘Second, my best friend and crush is being stalked by crazy, murderous psychos.’
    • ‘Kleptomaniacs, kitchen drinkers, Fatal Attraction type psychos, obsessive-compulsives, and other problem individuals are usually discovered in this phase.’
    • ‘It's unpleasant, but it's more unpleasant to be faced with true psychos / junkies on the subway.’
    • ‘I don't want to be put in there with a bunch of crazy psychos… I'm not a bad person.’
    madman, madwoman, mad person, deranged person, maniac, lunatic, psychotic, sociopath
    View synonyms

adjective

informal
  • Psychopathic.

    • ‘I would come back and watch all my favourite violent psycho movies.’
    • ‘I love blood and gore and crazed psycho killers come back from the dead.’
    • ‘They were scrawny but muscly trashy types, like my in-and-out, in-and-out of prison psycho cousin.’
    • ‘Next is Melanie, doing that psycho laugh of hers from the old days.’
    • ‘I always thought that those psycho girls who stalked band members and actors were just make believe, until now.’

Origin

1930s: abbreviation.

Pronunciation:

psycho

/ˈsʌɪkəʊ/