whispering dome

from WordNet (r) 3.0 (2006)
whispering dome
    n 1: a space beneath a dome or arch in which sounds produced at
         certain points are clearly audible at certain distant
         points [syn: {whispering gallery}, {whispering dome}]
    
from The Collaborative International Dictionary of English v.0.48
Whispering \Whis"per*ing\,
   a. & n. from {Whisper}. v. t.
   [1913 Webster]

   {Whispering gallery}, or {Whispering dome}, one of such a
      form that sounds produced in certain parts of it are
      concentrated by reflection from the walls to another part,
      so that whispers or feeble sounds are audible at a much
      greater distance than under ordinary circumstances. The
      dome of the U. S. capitol building is one example.
      [1913 Webster +PJC]
    

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