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

Derived Forms

• tachometrically
  adverb
• tachometry
  noun
• tachometric
  adjective

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

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

From Los Angeles Times • Mar. 10, 2022

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

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