| idiotic(adjective, silly, foolish, stupid) |
| mad as a hatter(expression, adjective, idiom, silly) |
| screwy(adjective, slang, silly, foolish, stupid) |
| barmy(silly, foolish, insane, unwise) |
| bats in the belfry(expression, idiom, silly, foolish) |
| delirious(adjective, silly, foolish, insane) |
| flipped out(expression, silly, foolish, insane) |
| freaked out(expression, silly, foolish, insane) |
| mad as a March hare(expression, idiom, silly, foolish) |
| mentally strange(expression, silly, foolish, insane) |
| nutty as fruitcake(expression, idiom, silly, foolish) |
| out to lunch(expression, idiom, silly, insane) |
| round the bend(expression, idiom, silly, foolish) |
| screw loose(expression, silly, foolish, insane) |
| silly(adjective, soft, tender, sweet, wild) |
| wacky(adjective, slang, silly, foolish) |
| ape(silly, foolish, insane, unwise) |
| berserk(silly, foolish, insane, unwise) |
| dingy(silly, foolish, insane, unwise) |
| dippy(silly, foolish, insane, unwise) |