roarer

from WordNet (r) 3.0 (2006)

roarer
    n 1: someone who communicates vocally in a very loud voice [syn:
         {roarer}, {bawler}, {bellower}, {screamer}, {screecher},
         {shouter}, {yeller}]

from The Collaborative International Dictionary of English v.0.48

Roarer \Roar"er\, n.
   1. One who, or that which, roars. Specifically:
      (a) A riotous fellow; a roaring boy.
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                A lady to turn roarer, and break glasses.
                                                  --Massinger.
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      (b) (Far.) A horse subject to roaring. See {Roaring}, 2.
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   2. (Zool.) The barn owl. [Prov. Eng.]
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