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.

---

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

---

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

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

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

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.