| delirious(adjective, silly, foolish, crazy) |
| flaky(adjective, silly, foolish, crazy) |
| bats in the belfry(expression, idiom, silly, foolish) |
| berserk(adjective, silly, foolish, crazy) |
| erratic(silly, foolish, insane, unwise) |
| flake(noun, slang, sick, mad person) |
| flipped(silly, foolish, insane, unwise) |
| flipped out(expression, silly, foolish, crazy) |
| freaked out(expression, silly, foolish, insane) |
| mad as a March hare(expression, idiom, silly, foolish) |
| mad as a hatter(expression, adjective, idiom, silly, foolish) |
| mentally strange(expression, silly, foolish, insane) |
| neurotic(noun, adjective, crazy, queer) |
| nutty as fruitcake(expression, idiom, silly, foolish) |
| schizophrenic(noun, adjective, wrong, silly, foolish) |
| screw loose(expression, silly, foolish, insane) |
| demoniac(noun, schizophrenic, maniac, madman) |
| dingy(silly, foolish, insane, unwise) |
| psychopath(noun, patient, lunatic, loony) |
| scatterbrain(noun, schizophrenic, maniac, madman) |