1769, from Latin raucus "hoarse," related to ravus "hoarse," from PIE echoic base *reu- "make hoarse cries" (cf. Sanskrit rayati "barks," ravati "roars;" Greek oryesthai "to howl, roar;" Latin racco "a roar;" Old Church Slavonic rjevo "I roar;" Lithuanian rekti "roar;" Old English rarian "to wail, bellow"). Middle English had rauc in the same sense, from the same source.