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[ta-kom-i-ter, tuh-] /tæˈkɒm ɪ tər, tə-/
any of various instruments for measuring or indicating velocity or speed, as of a machine, a river, or the blood.
an instrument measuring revolutions per minute, as of an engine.
Origin of tachometer
1800-10; tacho- + -meter
Related forms
[tak-uh-me-trik-lee] /ˌtæk əˈmɛ trɪk li/ (Show IPA),
tachometry, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for tachometer
  • The speedometer, tachometer and fuel gauges are all important.
  • Dashboard houses a kilowatt power meter instead of a tachometer.
  • The big, round traditional tachometer is cheek-by-jowl with a cheap-looking rectangle with digital readouts.
  • There are a few changes inside, too, including touches such as blue lighting inside the tachometer ring.
  • Because there is no tachometer, you shift when the power falls off.
  • Activity where students will understand the function of a tachometer and compare car versus airplane tachometers.
  • By using a tachometer to measure actual motor speed, it is possible to calculate motor loads.
  • The licensee noted that the digital tachometer for operation of reactor core isolation cooling had a dead battery.
  • The pressure distributor shall be equipped with a tachometer registering the pump speed pressure gauge, and a volume gauge.
  • Detection of this condition is accomplished by a friction driven tachometer driven from the hoist ropes.
British Dictionary definitions for tachometer


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
Derived Forms
tachometric (ˌtækəˈmɛtrɪk), tachometrical, adjective
tachometrically, adverb
tachometry, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for tachometer

1810, from Greek tachos "speed" + -meter.

Online Etymology Dictionary, © 2010 Douglas Harper
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tachometer in Medicine

tachometer ta·chom·e·ter (tā-kŏm'ĭ-tər, tə-)
An instrument used to measure the rotations per minute of a rotating shaft.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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