Rayleigh disk: Meaning and Definition of

Ray'leigh disk"

Pronunciation: [key]
— Acoustics, Mech.
  1. a small circular disk, usually of mica, that is suspended from a fiber and tends to be deflected at right angles to a stream of air, indicating by its deflection the intensity of a sound wave.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.