ta·​chom·​e·​ter | \ ta-ˈkä-mə-tər , tə-\

Definition of tachometer

: a device for indicating speed of rotation

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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

To be a decent street engine, the Valkyrie's had to make a solid chunk of its power much lower on the tachometer. Matthew Jancer, Popular Mechanics, "Pride of the Valkyries," 29 Jan. 2019 One of my favorite features, and this is rolling out in most GM cars, is the selectable display in the instrument cluster between the tachometer and speedometer. Robert Duffer, chicagotribune.com, "Auto review: 2017 Buick LaCrosse is a good car at a bad time," 15 Aug. 2017 In sport mode, the display changes to show an analog tachometer. Eric Bangeman, Ars Technica, "Luxury on a budget: The Lexus NX 300h hybrid reviewed," 14 Oct. 2018 That low-end grunt lets the CT6 move effortlessly around town and hustle up highway on-ramps without having to rev to the screaming high end of the tachometer. Matthew Jancer, Popular Mechanics, "Why GM Finally Let Cadillac Build an All-New Twin-Turbo V8," 28 Aug. 2018 Ahead of you, the main instrument display is a pair of physical analog gauges (tachometer on the left, speedometer on the right) with a small multifunction display in between. Jonathan M. Gitlin, Ars Technica, "The Nissan Rogue is a huge sales success, but is it any good? A review," 18 Apr. 2018 An analog tachometer and temperature gauge are to the left, while the right dial shows battery, temperature, and fuel. Eric Bangeman, Ars Technica, "Review: Buick aims high, falls short with $60,000 Enclave Avenir," 2 Mar. 2018 The analog tachometer is flanked by two 7-inch screens. Robert Duffer, chicagotribune.com, "2017 Porsche Panamera is quick and nice for a steep steep price," 18 Sep. 2017 The energy meter in the tachometer, delineated by a drop icon for gas and a bolt icon for electric, is really the only way to sense the subtle shift of energy sources. Robert Duffer, chicagotribune.com, "Volvo surges ahead of competition with XC60 plug-in hybrid," 6 Dec. 2017

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.

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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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Last Updated

18 Feb 2019

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Time Traveler for tachometer

The first known use of tachometer was in 1810

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English Language Learners Definition of tachometer

technical : a device that measures how fast something (such as a wheel) is turning

More from Merriam-Webster on tachometer

Rhyming Dictionary: Words that rhyme with tachometer

Britannica.com: Encyclopedia article about tachometer

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