"to emit soft, rapid sounds," late 14c. (implied in rustling), of uncertain origin, perhaps imitative (cf. M.L.G. ruschen, M.Du. ruusscen, Ger. rauschen "to rustle"). The noun is attested from 1759. Meaning "steal" (especially cattle) first attested 1882, probably from earlier Amer.Eng. slang sense of "move about vigorously" (1872), perhaps a separate word, compounded from rush and hustle.