A shiny brown nut from a horse chestnut tree, often strung on a string and used in the children's game of conkers.
Possibly from 'conquer' (because hitting an opponent's conker with yours 'conquers' it) or from obsolete 'conquer' meaning snail shell. The game and word became popular in Britain in the Victorian era.
The British game of conkers is a perfect example of how kids turn nature into entertainment—children have been playing this for over 150 years, hitting their chestnuts together to see whose breaks first, and it's still beloved in UK playgrounds!
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