A person involved in perpetrating a genocide.(noun)
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Use "genocidaire" in a sentence
"The final section of the film is set in Congo, where many Rwandan refugees fled to camps that were overseen by the so-called "genocidaire": gangs responsible for some of the Rwandan slaughter."
"And this joker is trying to pawn Baathist genocidaire Saddam Hussein off as being ‘right wing’."
"If you really want to see horribleness, check out what these people write about the greatest American genocidaire, Andrew Jackson."