Jealousy of loveless envoy (4)
I believe the answer is:
envy
'jealousy' is the definition.
(jealousy is an envious feeling)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for envy that I've seen before include "Green-eyed feeling" , "Feeling of grudging admiration" , "Desire to possess another's attributes etc" , "Desire as a rival" , "Jealousy, resentment" .)