<p><strong>noun</strong></p><ul><li>the act of a person, animal, or thing that roars.</li><li>a loud, deep cry or sound or a series of such sounds.</li><li>a disease of horses, caused by respiratory obstruction or vocal cord paralysis, and characterized by loud or rough breathing sounds.</li></ul><p><strong>adjective</strong></p><ul><li>making or causing a roar, as an animal or thunder.</li><li>brisk or highly successful, as trade: He did a roaring business selling watches to tourists.</li><li>characterized by noisy, disorderly behavior; boisterous; riotous: roaring revelry.</li><li>complete; utter; out-and-out: a roaring idiot; a roaring success.</li></ul><p><strong>adverb</strong></p><ul><li>very; extremely: roaring drunk.</li></ul>