Season -- time enough possibly (7)
I believe the answer is:
toughen
'season' is the definition.
(thesaurus)
'time enough possibly' is the wordplay.
'time' becomes 't'.
'possibly' indicates anagramming the letters.
'enough' with letters rearranged gives 'oughen'.
't'+'oughen'='TOUGHEN'
(Other definitions for toughen that I've seen before include "Strengthen, season" , "Make strong and durable" , "Make harder" , "Make stronger and hardier" , "Harden, strengthen" .)