Postpone being freed, possibly (5)
I believe the answer is:
defer
'postpone' is the definition.
(synonyms)
'freed possibly' is the wordplay.
'possibly' indicates anagramming the letters.
'freed' anagrammed gives 'DEFER'.
'being' acts as a link.
(Other definitions for defer that I've seen before include "Postpone - submit" , "Hold back to a later time" , "Put off or give way" , "Give precedence to" , "put on ice" .)