| kooky(adjective, weak, simple, wrong, wild) |
| loco(adjective, slang, crazy, mad, irrational) |
| mentally ill(expression, adjective, idiom, mad, sane) |
| moronic(adjective, weak, simple, knowledge, ability) |
| potty(adjective, wild, silly, foolish, stupid) |
| certifiable |
| inane(adjective, simple, foolish, crazy, fantastic) |
| mindless(adjective, foolish, mad, unreasonable, illogical) |
| unsound(adjective, wrong, silly, foolish, stupid) |
| brainless(adjective, weak, simple, silly, foolish) |
| crackers(adjective, simple, silly, foolish, disturbed) |
| eccentric(noun, adjective, wild, strange, silly) |
| frenetic(adjective, upset, violent, wild, mad) |
| goofy(adjective, silly, foolish, fantastic, unwise) |
| loopy(adjective, knowledge, ability, informal, foolish) |
| manic(adjective, evil, wild, stupid, hot) |
| mental patient(expression, person, insanity, craziness) |
| not all there(expression, adjective, idiom, crazy, unstable) |
| out to lunch(expression, adjective, idiom, silly, crazy) |
| witless(adjective, weak, simple, silly, foolish) |