Major entertained by popular general (5)
I believe the answer is:
'major' is the definition.
(I've seen this in another clue)
'entertained by popular general' is the wordplay.
'entertained by' says the answer is hidden in the clue.
'LARGE' can be found hidden inside 'popular general'.
(Other definitions for large that I've seen before include "One has liberty to be at it" , "Regal (anag)" , "Copious" , "Lager (anag.)" , "Bulky" .)