A literate design to get revenge (9)
I believe the answer is:
retaliate
'get revenge' is the definition.
(I've seen this in another clue)
'a literate design' is the wordplay.
'design' indicates anagramming the letters.
'a'+'literate'='aliterate'
'aliterate' is an anagram of 'RETALIATE'.
'to' acts as a link.
(Other definitions for retaliate that I've seen before include "Strike back, counter" , "Get revenge" , "Make tit-for-tat attack" , "Get one's own back" , "Fight back" .)