late 14c., nowghty, noughti "needy, having nothing," also "evil, immoral, unclean," from nought "evil, an evil act; nothingness; a trifle; insignificant person; the number zero" (from Old English nawiht "nothing;" see naught)) + -y (2).
Specific meaning "sexually promiscuous" is from 1869. The more tame main modern sense of "disobedient" (especially of children) is attested from 1630s. Related: Naughtily; naughtiness. A woman of bad character c. 1530-1750 might be called a naughty pack (also sometimes of men and later of children).