From The Collaborative International Dictionary of English v.0.48:
Roar \Roar\, v. i. [imp. & p. p. Roared; p. pr. & vvb. n. Roaring.] [OE. roren, raren, AS. r[=a]rian; akin to G. r["o]hten, OHG. r[=e]r[=e]n. [root]112.] 1. To cry with a full, loud, continued sound. Specifically: (a) To bellow, or utter a deep, loud cry, as a lion or other beast. [1913 Webster]
Roaring bulls he would him make to tame. --Spenser. [1913 Webster] (b) To cry loudly, as in pain, distress, or anger. [1913 Webster]
Sole on the barren sands, the suffering chief Roared out for anguish, and indulged his grief. --Dryden. [1913 Webster]
He scorned to roar under the impressions of a finite anger. --South. [1913 Webster]
2. To make a loud, confused sound, as winds, waves, passing vehicles, a crowd of persons when shouting together, or the like. [1913 Webster]
The brazen throat of war had ceased to roar. --Milton. [1913 Webster]
How oft I crossed where carts and coaches roar. --Gay. [1913 Webster]
3. To be boisterous; to be disorderly. [1913 Webster]
It was a mad, roaring time, full of extravagance. --Bp. Burnet. [1913 Webster]
4. To laugh out loudly and continuously; as, the hearers roared at his jokes. [1913 Webster]
5. To make a loud noise in breathing, as horses having a certain disease. See Roaring, 2. [1913 Webster]
Roaring boy, a roaring, noisy fellow; -- name given, at the latter end Queen Elizabeth's reign, to the riotous fellows who raised disturbances in the street. "Two roaring boys of Rome, that made all split." --Beau. & Fl.
Roaring forties (Naut.), a sailor's name for the stormy tract of ocean between 40[deg] and 50[deg] north latitude. [1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Roar \Roar\, v. t. To cry aloud; to proclaim loudly. [1913 Webster]
This last action will roar thy infamy. --Ford. [1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Roar \Roar\, n. The sound of roaring. Specifically: (a) The deep, loud cry of a wild beast; as, the roar of a lion. (b) The cry of one in pain, distress, anger, or the like. (c) A loud, continuous, and confused sound; as, the roar of a cannon, of the wind, or the waves; the roar of ocean. [1913 Webster]
Arm! arm! it is, it is the cannon's opening roar! --Byron. [1913 Webster] (d) A boisterous outcry or shouting, as in mirth. [1913 Webster]
Pit, boxes, and galleries were in a constant roar of laughter. --Macaulay. [1913 Webster]