late 15c., "shot, missiles;" later "a stroke in drawing, a short line" (1580s), from Middle French trait "line, stroke, feature, tract," from Latin tractus "drawing, drawing out, dragging, pulling," later "line drawn, feature," from past participle stem of trahere "to pull, draw" (see tract (n.1)). Sense of "particular feature, distinguishing quality" in English is first recorded 1752.
