| crazy(noun, fanatic, loony, dingbat, ultraist) |
| lunatic(noun, crazy, loony, worrier, nutter) |
| madman(noun, character, crazy, cuckoo, loony) |
| nutter(noun, neurotic, worrier, valetudinary) |
| loony |
| maniac |
| nut(noun, crazy, fanatic, loony, lamebrain) |
| kook(noun, crazy, fanatic, loony, dingbat) |
| nutcase(noun, character, loony, dissentient, lamebrain) |
| crackpot(noun, character, crazy, loony, dissentient) |
| psycho |
| psychopath |
| psychotic |
| screwball |
| ding-a-ling(noun, character, fanatic, dissentient, crackpot) |
| dingbat(noun, character, crazy, fanatic, loony) |
| eccentric(noun, character, crazy, loony, dissentient) |
| insane person(noun, expression, idiom, person, worrier) |
| madperson(noun, character, nut, dissentient, misfit) |
| oddball(noun, character, crazy, cuckoo, loony) |