Derive clean form of release (11)
I believe the answer is:
deliverance
'release' is the definition.
(thesaurus)
'derive clean form' is the wordplay.
'form' indicates anagramming the letters.
'derive'+'clean'='deriveclean'
'deriveclean' anagrammed gives 'DELIVERANCE'.
'of' is the link.
(Other definitions for deliverance that I've seen before include "Liberation, release" , "Recovery from danger" , "Formal pronouncement" , "Formal utterance" , "Salvation" .)