| nutty as fruitcake(expression, idiom, silly, foolish, mad) |
| off one's head(expression, adjective, idiom, crazy, mad) |
| outlandish(adjective, unusual, strange, silly, foolish) |
| outrageous(adjective, silly, foolish, ridiculous, absurd) |
| pathetic |
| pointless(adjective, silly, stupid, insignificant, ridiculous) |
| purposeless(adjective, silly, stupid, insignificant, ridiculous) |
| rash(adjective, crazy, mad, odd, insane) |
| reckless(adjective, crazy, mad, odd, insane) |
| remarkable(unusual, strange, unexpected) |
| risible |
| screw loose(expression, silly, foolish, mad, insane) |
| singular(unusual, strange, odd, weird, unexpected) |
| soft |
| thoughtless(silly, crazy, unwise) |
| unconventional(unusual, strange, crazy, odd, weird) |
| undue |
| unintelligent(adjective, weak, simple, silly, foolish) |
| unnatural(unusual, strange, unexpected) |
| unstable(careless, foolish, stupid, unreasonable, unthinking) |