Enid’s wrong to be nasty (5)
I believe the answer is:
snide
'be nasty' is the definition.
(I've seen this in another clue)
'enid's wrong' is the wordplay.
'wrong' indicates an anagram.
'enids' with letters rearranged gives 'SNIDE'.
'to' is the link.
(Other definitions for snide that I've seen before include "Maliciously derogatory" , "Dines (anag.)" , "Derogatory in an insinuating way" , "Maliciously mocking" , "Delivering cuts" .)