Definition of costard in English:

costard

noun

(also Costard)
  • 1British A cooking apple of a large ribbed variety.

    • ‘The cooking equivalent was the Costard, which gave rise to the term costermonger, first applied to apple salesmen.’
    1. 1.1 archaic, humorous A person's head.
      skull, cranium, crown

Pronunciation

costard

/ˈkästərd/ /ˈkɑstərd/

Origin

Middle English from Anglo-Norman French, from coste ‘rib’, from Latin costa.