Rewritten epitaphs are most favourable (8)
I believe the answer is:
happiest
'most favourable' is the definition.
Both the answer and definition are superlative adjectives. Perhaps they are linked in a way I don't understand?
'rewritten epitaphs' is the wordplay.
'rewritten' indicates an anagram.
'epitaphs' anagrammed gives 'HAPPIEST'.
'are' is the link.
Can you help me to learn more?
(Other definitions for happiest that I've seen before include "Most contented and satisfied" , "Most content" , "Most gay" , "Gladdest" , "extremely contented" .)