Definition of "transducer" [transducer]

• A substance or device, such as a piezoelectric crystal, microphone, or photoelectric cell, that converts input energy of one form into output energy of another. (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.

• "The human ear cannot hear these echoes, so a special wand called a transducer is used."
• "The technician skidded a rodlike device, called a transducer, across my abdomen and pictures of my uterus were flashed onto the monitor."
• "The major breakthrough was Martin Rodbell's realization that there was a switch between these two steps, and that this switch, which he called the transducer, could be turned on by a high-energy compound, guanosine triphosphate."