Pass with extra study (8)
I believe the answer is:
overtake
'pass' is the definition.
(I know that pass can be written as overtake)
'with extra study' is the wordplay.
'with' says to put letters next to each other.
'extra' becomes 'over' (both can mean left over).
'study' becomes 'take' (synonyms).
'over' put next to 'take' is 'OVERTAKE'.
(Other definitions for overtake that I've seen before include "Pass the car in front" , "Catch up with and pass" , "Travel past" , "Pass (a vehicle)" , "Go past another person in a race" .)