Source : Webster's Revised Unabridged Dictionary (1913)

Whispering \Whis"per*ing\,
   a. & n. from {Whisper}. v. t.

   {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.

Source : WordNet®

whispering dome
     n : a space beneath a dome or arch in which sounds produced at
         certain points are clearly audible at certain distant
         points [syn: {whispering gallery}]