Dictator is human, no saint (5)
I believe the answer is:
peron
'dictator' is the definition.
(Argentine dictator Juan Pern)
'human no saint' is the wordplay.
'human' becomes 'person' (synonyms).
'no' is a deletion indicator.
'saint' becomes 's'.
'person' with 's' removed is 'PERON'.
'is' acts as a link.
(Other definitions for peron that I've seen before include "Juan ---, Argentine dictator" , "Former Argentine leader" , "Former Argentinian leader" , "Juan, maybe" , "Prone to being an Argentine president" .)