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

Sport: tachometer front and center with your digital speed slightly to the upper right.

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

It had been suggested that the revolutions in Africa occurred so often that only a tachometer could keep up with them.

From Hail to the Chief by Schoenherr, John