Numbers game, British? Popular move (5)
I believe the answer is:
bingo
'numbers game' is the definition.
(I've seen this in another clue)
'british? popular move' is the wordplay.
'british?' becomes 'b' (abbreviation e.g. in 'BBC').
'popular' becomes 'in' ('in' can mean trendy).
'move' becomes 'go' (to go is to move).
'b'+'in'+'go'='BINGO'
(Other definitions for bingo that I've seen before include "Popular gambling game in which numbers are called at random" , "Number-calling game" , "Voila!" , "Game of chance" , "Cry on discovering something" .)