Full relief after only 50 per cent relief brings freedom (7)
I believe the answer is:
release
'freedom' is the definition.
(thesaurus)
'full relief after only 50 per cent relief' is the wordplay.
'full relief' becomes 'ease' (I've seen this before. I am not sure about the 'full' bit.).
'after' says to put letters next to each other.
'only 50 per cent' suggests halving the letters.
'relief' cut in half is 'rel'.
'ease' put after 'rel' is 'RELEASE'.
'brings' is the link.
(Other definitions for release that I've seen before include "Free from confinement" , "Prisoner eagerly awaits this" , "Free - delivery" , "press announcement" , "New film" .)