tuning fork: Meaning and Definition of

tun'ing fork"

Pronunciation: [key]
  1. a steel instrument consisting of a stem with two prongs, producing a musical tone of definite, constant pitch when struck, and serving as a standard for tuning musical instruments, making acoustical experiments, and the like.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.