Type of billiards (7)
I believe the answer is:
snooker
'type of billiards' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for snooker that I've seen before include "Ballgame" , "Potting game" , "Cue sport" , "Tabletop game" , "A form of pool" .)