tachometer

American  

[ta-kom-i-ter, tuh-] / tæˈkɒm ɪ tər, tə- /

noun

1. any of various instruments for measuring or indicating velocity or speed, as of a machine, a river, or the blood.

2. an instrument measuring revolutions per minute, as of an engine.

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tachometer British  

/ ˌtækəˈmɛtrɪk, tæˈkɒmɪtə /

noun

1. any device for measuring speed, esp the rate of revolution of a shaft. Tachometers (rev counters) are often fitted to cars to indicate the number of revolutions per minute of the engine

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Other Word Forms

• tachometric adjective
• tachometrically adverb
• tachometry noun

Etymology

Origin of tachometer

First recorded in 1800–10; tacho- + -meter

Example Sentences

Upshift with the tachometer at 2,000 to 2,500 rpm, not 3,000, Toyota advises.

From Los Angeles Times • Mar. 10, 2022

I was a meter with a normal range, like a tachometer, and I had to avoid straying too far into the red.

From Salon • Jul. 21, 2019

A conventional dash with all its gauges in place, save a single unit in place of the tachometer to relay the electrical goings-ons, will be an option on retrofitted vehicles.

From New York Times • Sep. 6, 2018

Allow your eyes to dip down briefly to the tachometer.

From The Verge • Feb. 9, 2016

The motor worked smoothly, the hand of the tachometer wavering around twelve hundred, and the altometer registering nine thousand feet, save when they dipped and lifted to the uneven currents over the mountains.

From The Thunder Bird by Bower, B. M.