1590s, "out of the common or direct way," from Latin devius "out of the way, remote, off the main road," from de via; from de "off" (see de-) + via "way, road" (see via). Compare deviate. Originally in the Latin literal sense; the figurative sense of "deceitful" is first recorded 1630s. Related: Deviously; deviousness. Figurative senses of the Latin word were "retired, sequestered, wandering in the byways, foolish, inconsistent."