Game played in Great Britain for food (4)
I believe the answer is:
grub
'for food' is the definition.
(grub can informally mean food)
'game played in great britain' is the wordplay.
'game played' becomes 'RU' (rugby union).
'in' indicates putting letters inside.
'great britain' becomes 'gb'.
'ru' placed within 'gb' is 'GRUB'.
(Other definitions for grub that I've seen before include "Nosh - larva" , "Table needs" , "Slangy food or kind of larva" , "Slang food for worm-like larva" , "Dig - maggot - food" .)