Noun
the virus that causes smallpox in humans; can be used as a bioweapon
Source: WordNetIt is fashionable to wax apocalyptic about the threat to humanity posed by the AIDS virus, "mad cow" disease, and many others, but I think a case can be made that faith is one of the world's great evils, comparable to the smallpox virus but harder to eradicate. Richard Dawkins
Most of the trouble in this world has been caused by folks who can't mind their own business, because they have no business of their own to mind, any more than a smallpox virus has. William S. Burroughs