| dumb |
| empty-headed |
| flipped(silly, foolish, mad, insane, unwise) |
| flipped out(expression, silly, foolish, crazy, mad) |
| freaked out(expression, silly, foolish, crazy, mad) |
| fruity(silly, foolish, mad, insane, unwise) |
| giddy(noun, adjective) |
| half-baked(weak, simple, silly, foolish, thoughtless) |
| half-witted(weak, simple, silly, foolish, thoughtless) |
| ill-advised(adjective, weak, simple, silly, foolish) |
| ill-considered(adjective, weak, simple, silly, foolish) |
| mad as a March hare(expression, idiom, silly, foolish, mad) |
| mad as a hatter(expression, idiom, silly, foolish, mad) |
| mentally strange(expression, silly, foolish, mad, insane) |
| nutty as fruitcake(expression, idiom, silly, foolish, mad) |
| of unsound mind(expression, adjective, idiom, silly, foolish) |
| round the bend(expression, idiom, silly, foolish, mad) |
| screw loose(expression, silly, foolish, mad, insane) |
| thoughtless(silly, unwise) |
| unearthly(adjective, knowledge, ability) |