Restrain rookie trapping rook (4)
I believe the answer is:
curb
'restrain' is the definition.
('curb' can be a synonym of 'restrain')
'rookie trapping rook' is the wordplay.
'rookie' becomes 'cub' ('cub' can be a synonym of 'rookie').
'trapping' indicates putting letters inside.
'rook' becomes 'r' (abbreviation in chess).
'cub' going around 'r' is 'CURB'.
(Other definitions for curb that I've seen before include "[LIMITATION]" , "Bit - restraint" , "Hold back or try to prevent" , "Control, limit" , "Constrain" .)