May get out of prison sentence? (10)
I believe the answer is:
springtime
'may' is the definition.
(springtime includes May)
'get out of prison sentence?' is the wordplay.
'get out of prison' becomes 'spring' (I've seen this before).
'sentence?' becomes 'time' (I've seen this before).
'spring'+'time'='SPRINGTIME'
(Other definitions for springtime that I've seen before include "era of promise" , "Season loved by lovers" , "Growing season" , "When trees are budding" .)