Fruit grasped by agile monkey (5)
I believe the answer is:
lemon
'fruit' is the definition.
(lemon is a kind of fruit)
'grasped by agile monkey' is the wordplay.
'grasped by' indicates a hidden word.
'LEMON' is hidden within 'agile monkey'.
(Other definitions for lemon that I've seen before include "Fruit high in vitamin C" , "Something worthless" , "Fruit - as an answer it's unsatisfactory" , "Sharp-tasting fruit" , "Pulsate" .)