cap in hand

back of one's hand

A display of disrespect or scorn.

bear a hand

To make haste; to help quickly.

big hand

Synonym of minute hand (on a clock face).

bite someone's hand off

To enthusiastically accept an offer.

bite the hand that feeds one

To cause harm to a benefactor (especially one that one is dependent on, thus with the idea that this behaviour is self-damaging).

bust a cap

To fire a weapon; to shoot with a gun.

cap it all off

To finish or complete something; to add a finishing touch.

cap over the windmill

In a bizarre or eccentric manner.