1590s, "a wandering, act of straying," from Latin aberrationem (nominative aberratio) "a wandering," noun of action from past-participle stem of aberrare "to wander out of the way, lose the way, go astray," literally and figuratively, from ab "off, away from" (see ab-) + errare "to wander, stray, roam, rove" (see err). Meaning "deviation from the normal type" is attested by 1735.