acoustic thermometry

noun

: a technique for measuring the temperature of something (such as a region of ocean water) by measuring how long it takes sound to travel through it

Because sound travels faster in warm water than in cold, this method, called acoustic thermometry, could provide a precise method of taking the ocean's temperature, they reasoned.

—R. Monastersky, Science News, 29 Aug. 1998

Note: The speed of sound through a substance changes in a predictable way as the temperature of the substance changes. By timing a pulse of sound as it passes through a substance, it is possible to determine exactly how warm or cold the substance is.

acoustic thermometer noun

The acoustic thermometer works by transmitting sound waves along a gas-filled tube from a speaker at one end to a microphone at the other. By measuring the amount of time it takes the sound waves to travel along the tube, the temperature can be calculated.

—Advanced Materials & Processes, 1 July 2011

Word History

First Known Use

1962, in the meaning defined above

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