tachometer

noun
ta·​chom·​e·​ter | \ ta-ˈkä-mə-tər How to pronounce tachometer (audio) , tə- \

Definition of tachometer

: a device for indicating speed of rotation

Did you know?

A tachometer is literally a "speed-measurer", since the Greek root tach- means "speed". This is clear in the names of the tachyon, a particle of matter that travels faster than the speed of light (if it actually exists, it's so fast that it's impossible to see with any instrument), and tachycardia, a medical condition in which the heart races uncontrollably. Since the speed that an auto tachometer measures is speed of rotation of the crankshaft, the numbers it reports are revolutions per minute, or rpm's.

Examples of tachometer in a Sentence

Recent Examples on the Web Upshift with the tachometer at 2,000 to 2,500 rpm, not 3,000, Toyota advises. Tribune News Service, oregonlive, 13 Mar. 2022 Upshift with the tachometer at 2,000 to 2,500 rpm, not 3,000, Toyota advises. Tribune News Service, oregonlive, 13 Mar. 2022 Upshift with the tachometer at 2,000 to 2,500 rpm, not 3,000, Toyota advises. Tribune News Service, oregonlive, 13 Mar. 2022 Upshift with the tachometer at 2,000 to 2,500 rpm, not 3,000, Toyota advises. Tribune News Service, oregonlive, 13 Mar. 2022 The instrument cluster features an analog speedometer and a digital tachometer that looks like the readout of a graphic equalizer. Elana Scherr, Car and Driver, 2 Aug. 2021 The Rebel Machine features a tachometer on the hood. WSJ, 19 Mar. 2022 Upshift with the tachometer at 2,000 to 2,500 rpm, not 3,000, Toyota advises. Tribune News Service, oregonlive, 13 Mar. 2022 Most of that seems to be wind and tire noise, the straight-six emitting no more than a distant thrum from somewhere beyond the firewall, happily firing the gargantuan Chevy down the road while the tachometer needle hangs out down near idle. Ezra Dyer, Car and Driver, 20 Aug. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tachometer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of tachometer

1810, in the meaning defined above

History and Etymology for tachometer

Greek tachos speed + English -meter

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Time Traveler for tachometer

Time Traveler

The first known use of tachometer was in 1810

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Dictionary Entries Near tachometer

tachograph

tachometer

tachometrically

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Statistics for tachometer

Last Updated

11 May 2022

Cite this Entry

“Tachometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tachometer. Accessed 24 May. 2022.

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More from Merriam-Webster on tachometer

Britannica.com: Encyclopedia article about tachometer

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