| of unsound mind(expression, idiom, silly, foolish) |
| bats in the belfry(expression, idiom, silly, foolish) |
| flipped out(expression, silly, foolish, insane) |
| freaked out(expression, silly, foolish, insane) |
| mad as a March hare(expression, idiom, silly, foolish) |
| mad as a hatter(expression, idiom, silly, foolish) |
| mentally strange(expression, silly, foolish, insane) |
| nutty as fruitcake(expression, idiom, silly, foolish) |
| out to lunch(expression, idiom, silly, foolish) |
| round the bend(expression, idiom, silly, foolish) |
| screw loose(expression, silly, foolish, insane) |
| ape(silly, foolish, insane, unwise) |
| barmy(silly, foolish, insane, unwise) |
| batty(silly, foolish, insane, unwise) |
| berserk(silly, foolish, insane, unwise) |
| bonkers(silly, foolish, insane, unwise) |
| cracked(silly, foolish, insane, unwise) |
| crazed(silly, foolish, insane, unwise) |
| cuckoo(silly, foolish, insane, unwise) |
| daft(silly, foolish, insane, unwise) |