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

The effective head-up display will show, depending on operator selection, speed, speed limit, tachometer, compass and other things.

From Los Angeles Times • May 6, 2016

He lost radio communication with his team at one point, his tachometer broke and his engine grew hot enough that water was spewing from under the hood.

From Washington Post • Feb. 28, 2012

The tachometer operates on the same principle as the speed indicating device or speedometer used in automobiles except that the dial is calibrated to show revolutions per minute instead of miles per hour.

From Aviation Engines Design?Construction?Operation and Repair by Pag?, Victor Wilfred