conker

noun

conk·​er ˈkäŋ-kər 

1

: a horse chestnut especially when used in conkers

2

conkers plural : a game in which each player swings a horse chestnut on a string to try to break one held by the opponent

Word History

Etymology

conch + -er entry 2, from the original use of a snail shell on a string in the game

First Known Use

circa 1886, in the meaning defined at sense 1