as mad as a hatter
疯疯癫癫的，疯狂的
口语·形容疯狂或古怪
英文释义
to be crazy or insane
例句
He's as mad as a hatter, talking to himself and wearing mismatched shoes.
典故来源
源自19世纪制帽业，制帽工人长期接触水银导致神经受损，行为怪异，后比喻疯狂。