Deliberate derailer (8)

I believe the answer is:

saboteur

(Other definitions for saboteur that I've seen before include "Abuser to become a kind of destroyer" , "Oen who causes industrial damage for pay" , "Political wrecker" , "Rebel" , "Wrecker -- sour beat (anag)" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.