c. 1400, deviaunt, "different, deviating, straying, wandering," from Late Latin deviantem (nominative devians), present participle of deviare "turn aside," from Latin phrase de via, from de "off" (see de-) + via "way" (see via). The noun meaning "one that deviates, one who goes astray" is from 1540s. It is attested by 1927 as "something that deviates from normal." In the sexual sense "person whose sexuality deviates from what is held to be normal," from 1952. Also compare deviate (n.), recorded in that sense since 1912.