Abel to us might be perfect (8)
I believe the answer is:
absolute
'perfect' is the definition.
(synonyms)
'abel to us might be' is the wordplay.
'might be' indicates anagramming the letters.
'abel'+'to'+'us'='abeltous'
'abeltous' anagrammed gives 'ABSOLUTE'.
(Other definitions for absolute that I've seen before include "Unlimited (power)" , "Unqualified; Sheridan's Sir Anthony" , "Complete, full" , "Total or final" , "Complete - unlimited" .)