psycho
adj//ˈsaɪ̯.koʊ̯//psykopatisk, tokig, vansinnig, psyk, psykfall, psyko, galning
(colloquial, or, pejorative) Psychotic, psychopathic, or (broadly) otherwise insane.
(chiefly, derogatory, slang) A person who is psychotic, psychopathic, or (broadly) otherwise insane.
(chiefly, derogatory, slang, broadly) A person who acts in a bizarre or dangerous manner.