I've had the misfortune to have several of my daily mailings flagged as spam by ~cop or ~assassin for containing words that merely contain possibly offensive *memes. also, I once was flagged for including the word "God" in a citation from one of William F. Buckley's books.

I don't think I'd use the word assassin in a mailing, even were I to find a *really obscure term for assassin in the OED.