thermometer

noun

ther·​mom·​e·​ter thər-ˈmä-mə-tər How to pronounce thermometer (audio)
thə-ˈmä-mə-tər
plural thermometers
: an instrument for determining temperature
specifically : one consisting of a sensor housed in a metal probe that registers a change in electrical resistance as a change in temperature

Examples of thermometer in a Sentence

Recent Examples on the Web
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Michael checked his temperature; the thermometer read a hundred and five. Ruby Cramer, New Yorker, 31 Aug. 2026 The ice cream parlor’s Leawood location did not have a working food thermometer at the time of inspection, and no soap was found in the co-ed bathroom. Joseph Hernandez august 31, Kansas City Star, 31 Aug. 2026 Your ticket through triage Start with an accurate digital thermometer. Dr. Jill Grimes, CNN Money, 29 Aug. 2026 Raising the cost of baby products such as thermometers or formula for brand-new parents. Jack Dolan, Los Angeles Times, 27 Aug. 2026 See All Example Sentences for thermometer

Word History

Etymology

French thermomètre, from Greek thermē heat + French -o- + -mètre -meter — more at therm

First Known Use

1633, in the meaning defined above

Time Traveler
The first known use of thermometer was in 1633

Cite this Entry

“Thermometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thermometer. Accessed 1 Sep. 2026.

Kids Definition

thermometer

noun
: an instrument for measuring temperature

Medical Definition

thermometer

noun
: an instrument for determining temperature that usually consists either of a device providing a digital readout or of a glass bulb attached to a fine tube of glass with a numbered scale and containing a liquid (as mercury or colored alcohol) that is sealed in and rises and falls with changes of temperature

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