Definition of roar :
1. A boisterous outcry or shouting, as in mirth.
2. A loud, continuous, and confused sound; as, the roar of a cannon, of the wind, or the waves; the roar of ocean.
3. The cry of one in pain, distress, anger, or the like.
4. The deep, loud cry of a wild beast; as, the roar of a lion.
5. The sound of roaring.
6. To be boisterous; to be disorderly.
7. To bellow, or utter a deep, loud cry, as a lion or other beast.
8. To cry aloud; to proclaim loudly.
9. To cry loudly, as in pain, distress, or anger.
10. To cry with a full, loud, continued sound.
11. To laugh out loudly and continuously; as, the hearers roared at his jokes.
12. To make a loud noise in breathing, as horses having a certain disease. See Roaring, 2.
13. To make a loud, confused sound, as winds, waves, passing vehicles, a crowd of persons when shouting together, or the like.
shout, yowl, yaup, hollering, wrawl, exclaim, scag, whimper, mewl, yawp, holloa, godsend, hollow, manna from heaven, halloo, detonation, rumble, microphone boom, vociferate, windfall, yell, guffaw, hell dust, reverberation, bellowing, shriek, yawl, holler, thunder, pule, big H, gold rush, hollo, clash, whoop, holla, roaring, smack, break up, nose drops, gravy, bunce, skag, yammer, barrage, noise, explosion, bang, ejaculate, scream, laughter, bonanza
loudness (part of speech: noun)
blow (part of speech: verb)
rage (part of speech: verb)
ululate (part of speech: verb)
crow, chatter, cackle, snort, caw, growl, bleat, gobble, mew, neigh, meow, squawk, cry, whinny, cuckoo, grunt, bellow, bay, chirp, quack, snarl, cluck, moo, warble, honk, yelp, squeal, trill, twit, call, hoot, ululate, purr, howl, bawl, bray, coo, bark
ululation (part of speech: noun)
- And in the end of six more hours, I ceased to go upward, and did know of a strange low sound, that did be like to no other sound that ever I did hear; and was like to a dull roar that did never have ceased through eternity. - "The Night Land", William Hope Hodgson.
- Deep in some gulch could be heard the roar of a mountain stream. - "Last Words", Stephen Crane.
- The roar of battle continues. - "The Dynasts An Epic-Drama Of The War With Napoleon, In Three Parts, Nineteen Acts, And One Hundred And Thirty Scenes", Thomas Hardy.