Sin that sounds reducible to its core elements? (4)
I believe the answer is:
envy
'sin' is the definition.
(envy is a kind of sin)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for envy that I've seen before include "One of seven deadly sins" , "Feeling of grudging admiration" , "Covet; be jealous of" , "The green-eyed monster" , "Desire as a rival" .)