Disapprove strongly of silly old peer (7)
I believe the answer is:
deplore
'disapprove strongly' is the definition.
(I've seen this before)
'silly old peer' is the wordplay.
'silly' is an anagram indicator.
'old'+'peer'='oldpeer'
'oldpeer' anagrammed gives 'DEPLORE'.
'of' acts as a link.
(Other definitions for deplore that I've seen before include "Sorrow over" , "Lament" , "Express strong disapproval of (something)" , "Regret deeply and strongly disapprove" , "Condemn" .)