ta·​chom·​e·​ter | \ ta-ˈkä-mə-tər How to pronounce tachometer (audio) , 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 Between the tachometer and speedometer is a new, 7.0-inch display screen. Colin Beresford, Car and Driver, "2021 Nissan Armada Is Better-Looking, Gets New Technology," 8 Dec. 2020 Downshifts never upset the chassis; sometimes the only way to know if a downshift has occurred is to look at the tachometer. Tony Quiroga, Car and Driver, "Tested: 2006 Honda Civic Si vs. Volkswagen GTI," 18 Nov. 2020 These settings also reclock the Aston's center-mounted tachometer so that 6000 rpm is straight up and dial up the volume of its storming exhaust. Scott Oldham, Car and Driver, "2021 Aston Martin Vantage Roadster Cannot Be Ignored," 2 Oct. 2020 On the inside, a fuzzy dash pad covered most everything but the tachometer and speedometer. John Pearley Huffman, Car and Driver, "2022 Volkswagen Taos Previews an Important New Engine for VW," 6 Oct. 2020 The passenger compartment is similarly unchanged beyond the replacement of the tachometer in the digital instrument cluster with a power-flow meter. Mike Duff, Car and Driver, "2021 Volvo XC40 Recharge Puts Volvo in the EV Game," 2 Oct. 2020 Beyond the steering wheel is a large digital display that can be configured in a number of ways, including a traditional round tachometer. Jens Meiners, Car and Driver, "2021 Ferrari Roma Can Run as Well as It Can Pose," 9 Sep. 2020 Unfortunately, this large four-cylinder idles with the clatter of a diesel and is boomy through the top half of the tachometer. Scott Oldham, Car and Driver, "Tested: 2020 Cadillac CT4 450T AWD Qualifies as Mediocre," 14 Aug. 2020 And Ars readers will be glad to know there is not a single touchscreen in the T.50—all the controls are analog, as is the big tachometer directly in front of the driver. Jonathan M. Gitlin, Ars Technica, "Three seats, a V12, and a manual transmission: The GMA T.50 reveal," 4 Aug. 2020

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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Time Traveler for tachometer

Time Traveler

The first known use of tachometer was in 1810

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Statistics for tachometer

Last Updated

23 Jan 2021

Cite this Entry

“Tachometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tachometer. Accessed 25 Jan. 2021.

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More Definitions for tachometer


How to pronounce tachometer (audio)

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

Britannica.com: Encyclopedia article about tachometer

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