Some meagre winnings may be increased (4)
I believe the answer is:
grew
'be increased' is the definition.
(I've seen this before)
'some meagre winnings may' is the wordplay.
'some' indicates a hidden word (some parts of the word are used).
'GREW' is hidden in the letters of 'meagre winnings may'.
(Other definitions for grew that I've seen before include "Increased in size" , "Sprouted" , "Got bigger" , "Multiplied" , "Expanded - flourished" .)