[From Scots warlock (generalized in English from literary use by Scottish authors and replacing Early Modern English warlow), from alteration (with -ok for Middle English -ow as in Scots elbok, elbow, and windok, window) of Middle English warloghe, warlow, from Old English wǣrloga, oath-breaker : wǣr, pledge; see wērə-o- in the Appendix of Indo-European roots + -loga, liar (from lēogan, to lie; see leugh- in the Appendix of Indo-European roots).]