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

Watch as the graphically animated tachometer needle fans through a couple of full-power upshifts.

From The Wall Street Journal • Apr. 18, 2026

There are three customizable views that completely reconfigure the display: Normal: tachometer on the left, speedometer on the right, and customizable center for nav, current audio track, or cruise control info.

From The Verge • Aug. 8, 2022

This genre-defying book of compressed prose, poetry and image is the product of a mind — and heart — pushing the artistic tachometer to the red line.

From Washington Post • Dec. 22, 2021

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

A vibration tachometer which will indicate any speed between 50 and 150 rev. per sec., is directly connected to the drum, so that any chance of error by slipping is eliminated.

From Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 Federal Investigations of Mine Accidents, Structural Materials and Fuels. Paper No. 1171 by Wilson, Herbert M.