From King Dictionary of Contemporary English
Related topics: Plants
conkercon‧ker /ˈkɒŋkə $ ˈkɑːŋkər/ noun 1 HBP[countable] the large brown shiny seed of the horse chestnut tree2 conkers
Examples from the Corpus
conkerIn autumn, youngsters will be urged to collect conkers, ash keys and acorns to grow next year's seedlings.The winner is obviously the player with the intact conker.Players take it in turns to do this until one conker is so damaged that it is dislodged from its string.Naturally, the stronger and harder the conker, the more chance of success.Standing still was important for if the conker was swaying about, the striker had a free go.That's what my dreams showed - that underneath my standard teenage exterior I was conkers, stark staring.From my childhood I remember being told that the way to improve your conkers was to pickle them in vinegar.