| dotty(adjective, foolish) |
| fiend(noun, person, crazy, nut, fanatic) |
| goofy(adjective, foolish, impractical, half-baked, doomed) |
| harebrained(impractical, half-baked, doomed) |
| idiot(noun, fool) |
| idiotic(adjective, foolish, impractical, half-baked, doomed) |
| inane(adjective, foolish, impractical, half-baked, doomed) |
| kooky(adjective, eccentric, lunatic) |
| loco |
| madcap(noun, adjective, person, madness, insanity) |
| moronic(adjective, foolish, impractical, half-baked, doomed) |
| neurotic(noun, adjective, mad, lunatic, schizophrenic) |
| nutter |
| nutty(adjective, lunatic) |
| odd(adjective, crazy, mad, insane) |
| senseless(adjective, crazy, mad, odd, insane) |
| silly(adjective, impractical, half-baked, doomed) |
| witless(adjective, crazy, mad, odd, insane) |
| zany |
| asinine(adjective, foolish) |