Tuning fork (Mus.), a steel instrument consisting of two prongs and a handle, which, being struck, gives a certain fixed tone. It is used for tuning instruments, or for ascertaining the pitch of tunes.
... body sets up vibrations in another body, as for instance, when one tuning fork responds to the vibrations of another when both have the same ... — Marvels of Modern Science • Paul Severing
... paper, and the love of a mother for her child or a miser for his gold is no greater love than that, let me tell you. "You knew about this thing here?" He beat with two fingers that danced like the prongs of a tuning fork on the paper spread out in front of him. ... — The Escape of Mr. Trimm - His Plight and other Plights • Irvin S. Cobb