Definition of "tuning fork" []

• A small two-pronged metal device that when struck produces a sound of fixed pitch that is used as a reference, as in tuning musical instruments. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "His voice made up in genuine fervor what it lacked in volume, and the rabbi enjoyed his chanting with its traditional quavers and trills more than the studied effects of the cantor who surreptitiously would stoop and tap his tuning fork and hum the pitch before beginning a chant."
• "Students learn advanced hairspring manipulation, friction jeweling, disassembly, cleaning, and repair, electrical theory as it applies to watches and timepieces, and repairing tuning fork electronic movements."