Middle English roren, "shout out, cry out with a full, loud, continued sound," from Old English rarian "roar, wail, lament, bellow, cry," probably of imitative origin (compare Middle Dutch reeren, German röhren "to roar;" Sanskrit ragati "barks;" Lithuanian rieju, rieti "to scold;" Old Church Slavonic revo "I roar;" Latin raucus "hoarse," all alike probably imitative).
Of animals, the wind, etc., early 14c. Sense of "laugh loudly and continuously" is by 1815. The meaning "travel in a motor vehicle making a loud noise" is by 1923. Related: Roared; roaring.
late 14c., rore, "the loud, continued cry of a large beast," from roar (v.) and Old English gerar. Of other full, loud, continued, confused sounds by c. 1400; specifically of thunder and cannon by 1540s.
"that roars or bellows; making or characterized by noise or disturbance," late 14c., present-participle adjective from roar (v.). Used of periods of years characterized by noisy revelry, especially roaring twenties (1930, which OED credits to "postwar buoyancy"); but also, in Australia, roaring fifties (1892, in reference to the New South Wales gold rush of 1851). Roaring Forties in reference to exceptionally rough seas between latitudes 40 and 50 south, is attested from 1841.
The "roaring fifties" are still remembered as the days when Australia held a prosperity never equalled in the world's history and a touch of romance as well. The gold fever never passed away from the land. [E.C. Buley, "Australian Life in Town and Country," 1905]
Roaring boys, roaring lads, swaggerers : ruffians : slang names applied, about the beginning of the seventeenth century, to the noisy, riotous roisterers who infested the taverns and the streets of London, and, in general, acted the part of the Mohocks of a century later. Roaring girls are also alluded to by the old dramatists, though much less frequently. [Century Dictionary]
This is from the use of roar (v.) in old London slang for "behave in a riotous and bullying manner" (1580s).
"hoarse, harsh or croaking in sound," 1769, with -ous + Latin raucus "hoarse" (also source of French rauque, Spanish ronco, Italian rauco), from or related to ravus "hoarse," from Proto-Italic *rawo-, from PIE echoic base *reu- "to roar, make hoarse cries" (source also of Sanskrit rayati "barks," ravati "roars;" Greek oryesthai "to howl, roar;" Latin racco "a roar;" Old Church Slavonic rjevo "I roar;" Lithuanian rėkti "roar;" Old English rarian "to wail, bellow"). Middle English had rauc in the same sense, from Old French rauque and directly from Latin raucus.
"organized massacre in Russia against a particular class or people, especially the Jews," 1882, from Yiddish pogrom, from Russian pogromu "devastation, destruction," from po- "by, through, behind, after" (cognate with Latin post-; see post-) + gromu "thunder, roar," from PIE imitative root *ghrem- (see grim).