Crow and rook trapped by net (4)
I believe the answer is:
brag
'crow' is the definition.
(I know that crow is a more specific form of the action brag)
'rook trapped by net' is the wordplay.
'rook' becomes 'R' (chess abbreviation).
'trapped by' is an insertion indicator.
'net' becomes 'bag' (as a verb).
'r' placed within 'bag' is 'BRAG'.
'and' acts as a link.
(Other definitions for brag that I've seen before include "Card game, like poker" , "Talk boastfully" , "popular with 15 [EGOTIST] , no doubt" , "Boast ? card-game" , "Idle talk" .)