Possibly stroke male pigs bishop released on island (7)
I believe the answer is:
oarsman
'possibly stroke' is the definition.
(I know that stroke is a type of oarsman)
'male pigs bishop released on island' is the wordplay.
'male pigs' becomes 'boars' (a boar is a male pig).
'bishop' becomes 'B' (chess abbreviation).
'released' suggests deleting specific letters.
'on' says to put letters next to each other.
'island' becomes 'man' (the Isle of Man is an example).
'boars' with 'b' removed is 'oars'.
'oars'+'man'='OARSMAN'
(Other definitions for oarsman that I've seen before include "galley slave, say" , "One pulling in boat" , "He rows" , "Male rower" , "One in an eight?" .)