high jinks

Meanings

1. An old Scottish parlour game in which people were chosen, usually by throwing dice, to perform some humorous act or drink a large amount of an alcoholic beverage, with a forfeit if they were unable to do so.
2. Boisterous activity or behaviour; lively fun.
3. Tricky or waggish behaviour; mischief.

Etymology

Probably related to jink (“(verb) to make a quick evasive turn; to whirl about when dancing, to dance; (noun) a quick evasive turn”), probably originally onomatopoeic, expressing quick movement.