From Longman Dictionary of Contemporary Englishpsychopsy‧cho /ˈsaɪkəʊ $ -koʊ/ noun (plural psychos) [countable] informalMPVIOLENT someone who is mentally ill and who may behave in a violent or strange way —psycho adjective
Examples from the Corpus
psycho• For all I knew she might have been a psycho or a girl with a little blackmail on her mind.• Flesh-eating psycho played by Sir Anthony Hopkins is back in a slick, camp sequel.• These two raccoon-eyed psychos have lost none of their no-holds-barred energy or their penchant for writing catchy melodies.• When the psycho is caught, then let go on a technicality, Mom takes matters into her own hands.• All his posse friends were psychos, deranged misfits who were cruel for kicks.psycho-psycho- /saɪkəʊ, -kə $ -koʊ, -kə/ (also psych-) prefix technical MPrelating to the mind and the mental processes, rather than the body a psychoanalystPsychoPsycho (1960) a US horror film (=a film that is intended to make you feel frightened) made by Alfred Hitchcock. Its most famous scene is the one in which the character acted by Janet Leigh is killed with a knife by Norman Bates while she is in the shower.Origin psycho (1900-2000) psychopath 