Falsity
Usage notes
Instances may be quoted in abundance from old authors to show that the first three words are often strictly synonymous; but the modern tendency has been decidedly in favor of separating them, falsehood standing for the concrete thing, an intentional lie; falseness, for the quality of being guiltily false or treacherous: as, he is justly despised for his falseness to his oath; and falsity, for the quality of being false without blame: as, the falsity of reasoning. — the Century Dictionary, 1911.