make resentful (8)
I believe the answer is:
embitter
'make resentful' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for embitter that I've seen before include "Alienate" , "Make resentful and hostile" , "Make resentful or disillusioned" , "incense" , "cause resentment" .)