It’s sinful when unexploded in reverse (4)
Solution – Evil
A reversal type clue today. The definition part of the clue is “It’s sinful” – which matches “evil”.
“in reverse” is the hint or indicator that a reversal of letters is involved.
Another word for “unexploded” is “live” and if you reverse the letters you get “evil”.
For further discussion of reversal type clues, look in the sidebar under the list of popular posts for the list of cryptic crossword clue types.