Be resentful of English ivy on the borders (4)
I believe the answer is:
envy
'be resentful of' is the definition.
(I've seen this in another clue)
'ivy on the borders' is the wordplay.
'ivy' becomes 'English ivy' (synonyms).
'on the borders' says to hollow out the word (remove centre letters) (the edge/border letters).
'englishivy' with its centre taken out is 'ENVY'.
'english' acts as a link.
This may not be right. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for envy that I've seen before include "grudging discontent" , "The green-eyed emotion" , "Bad feeling" , "Desire of another's property etc" , "Feeling of discontent" .)