Given that Kleenex is just "Clean-X" and Xerox is just "Xero(graphy)-X" (they were known as Haloid before commercializing xerography and rebranding), those two

Given that Kleenex is just "Clean-X" and Xerox is just "Xero(graphy)-X" (they were known as Haloid before commercializing xerography and rebranding), those two names are actually just an "X" away from being generic.