1 mad, insane, psychopathic, deranged, demented, lunatic, paranoiac or paranoid, abnormal, unbalanced, (mentally) ill or esp. US sick, disturbed, non compos mentis, of unsound mind, exceptional, certifiable, daft, unhinged, raving, Slang crazy, nuts, nutty, loony or looney or luny, off one's rocker or trolley or chump or head, cracked, crack-brained, mental, out to lunch, batty, bats, having bats in one's belfry, having a screw loose, not all there, touched (in the head), bonkers:
The doctors diagnosed him as psychotic and insisted he be hospitalized.
2 madman, madwoman, maniac, psychopath, lunatic, paranoid or paranoiac, schizophrenic, bedlamite, Slang nut, nutter, screwball, crackpot, crazy, loony or looney or luny, schizo, US kook:
How many psychotics do you think are wandering about loose?