Elderly person lord set free (7)
I believe the answer is:
oldster
'elderly person' is the definition.
(I've seen this before)
'lord set free' is the wordplay.
'free' indicates anagramming the letters.
'lord'+'set'='lordset'
'lordset' anagrammed gives 'OLDSTER'.
(Other definitions for oldster that I've seen before include "He's more experienced" , "Mature person" , "One aged" , "Elderly person" , "Senior citizen (colloquial)" .)