1520s, "outbreak of disorder, revolt, commotion," used by Tindale and later Coverdale as a loan-translation of German Aufruhr or Dutch oproer "tumult, riot," literally "a stirring up," in German and Dutch bibles (as in Acts xxi.38). From German auf (Middle Dutch op) "up" (see up (adv.)) + ruhr (Middle Dutch roer) "a stirring, motion," related to Old English hreran "to move, stir, shake" (see rare (adj.2)). Meaning "noisy shouting" is first recorded 1540s, probably by mistaken association with unrelated roar.
-ous
word-forming element making adjectives from nouns, meaning "having, full of, having to do with, doing, inclined to," from Old French -ous, -eux, from Latin -osus (compare -ose (1)). In chemistry, "having a lower valence than forms expressed in -ic."
riproaring adj.
also rip-roaring, "full of vigour, spirit, or excellence" [OED], 1834, in affectations of Western U.S. (Kentucky) slang, altered from riproarious "boisterous, violent" (1821), from rip (v.) "tear apart" + uproarious; see uproar. Rip-roarer was noted as a nickname for a Kentuckian in 1837. Related: Riproaringest.