| absurd(silly, foolish, crazy, unwise) |
| bats in the belfry(expression, adjective, idiom, silly) |
| berserk(adjective, wild, enthusiastic, silly, foolish) |
| crazed(adjective, wild, silly, foolish, crazy) |
| crazy(adjective, wild, enthusiastic, strange, silly) |
| delirious(adjective, wild, enthusiastic, silly, foolish) |
| deranged(adjective, wild, enthusiastic, silly, foolish) |
| flipped(adjective, wild, enthusiastic, silly, foolish) |
| flipped out(expression, wild, silly, foolish, crazy) |
| frantic(adjective, wild, crazy, ill) |
| insane(adjective, wild, silly, foolish, crazy) |
| kooky(silly, foolish, crazy, insane) |
| mad as a March hare(expression, adjective, idiom, silly) |
| mad as a hatter(expression, adjective, idiom, silly) |
| mentally strange(expression, silly, foolish, insane) |
| nutty(adjective, wild, enthusiastic, silly, foolish) |
| nutty as fruitcake(expression, adjective, idiom, silly) |
| of unsound mind(expression, adjective, idiom, silly) |
| out to lunch(expression, adjective, idiom, silly) |
| rabid(adjective, wild, ill, sick) |