kronan

Etymology
Literally, "the coin."

Proper noun

 * 1) a game in which a coin is set spinning on its edge, with each player in turn then having to keep the coin spinning by flicking it (as well as keep it from going off the edge of the table or other playing surface); the loser of a round places his or her knuckles against the playing surface, and another player then flicks the coin against their knuckles, often resulting in bloodshed

Usage notes
Long widespread in Swedish elementary and high schools, though frequently banned.