con ‧ ker /ˈkɒŋkə $ ˈkɑːŋkər/ BrE AmE noun
1 . [countable] the large brown shiny seed of the ↑ horse chestnut tree
2 . conkers [uncountable] British English a children’s game in which conkers are hung from pieces of string and you try to break the other person’s conker by hitting it with your own