Merriam-Webster's Collegiate® Dictionary, 11th Edition
ROAR
I. verb
Etymology: Middle English roren, from Old English rārian; akin to Old High German rērēn to bleat Date: before 12th century intransitive verb
1. to utter or emit a full loud prolonged sound, to sing or shout with full force,
2. to make or emit a loud confused sound (as background re verb eration or rumbling), to laugh loudly,
3. to be boisterous or disorderly, to proceed or rush with great noise or commotion, to make a loud noise during inhalation (as that of a horse affected with roaring), transitive verb to utter or proclaim with a roar, to cause to roar,
II. noun
Date: 14th century
the deep cry of a wild animal (as a lion), a loud deep cry (as of pain or anger), a loud continuous confused sound , a boisterous outcry