saboteur[sab′ə tʉr′, -to̵or′]
saboteur definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
one who engages in sabotage
saboteur definition by American Heritage Dictionary
One who commits sabotage.
Origin: French, from saboter, to sabotage; see sabotage.