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
thermometric
ˌthər-mə-ˈme-trik How to pronounce thermometer (audio)
adjective
thermometrically
ˌthər-mə-ˈme-tri-k(ə-)lē How to pronounce thermometer (audio)
adverb

Examples of thermometer in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
According to official figures, even when the thermometer plummets to minus 22 °F (-30 °C), a situation that cripples most electric vehicles, the Atto 8 can still execute a 20 % to 97% charge in just 12 minutes. — New Atlas, 17 Oct. 2026 Rectal thermometers are preferred for children 3 and under; oral and digital infrared thermometers are both fine choices for anyone older than that. — Andee Tagle, NPR, 15 Oct. 2026 Roast until golden brown and thermometer registers 175°F, 30 to 45 minutes. — Sarah Martens, Better Homes & Gardens, 14 Oct. 2026 Grill the potatoes, cut sides down first, then flip with tongs, until golden brown, crispy on the edges, and easily punctured by a thermometer probe. — Candy Hom, AJC.com, 10 Oct. 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

Phrases Containing thermometer

Rhymes for thermometer

See All Rhymes for thermometer

Browse Nearby Words

thermometamorphism
thermometer
thermometer screen
See all Nearby Words

Cite this Entry

“Thermometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thermometer. Accessed 20 Oct. 2026.

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Kids Definition

thermometer

noun
ther·​mom·​e·​ter thə(r)-ˈmäm-ət-ər How to pronounce thermometer (audio)
: an instrument for measuring temperature
thermometric
ˌthər-mə-ˈme-trik How to pronounce thermometer (audio)
adjective

Medical Definition

thermometer

noun
ther·​mom·​e·​ter thə(r)-ˈmäm-ət-ər How to pronounce thermometer (audio)
: 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

More from Merriam-Webster on thermometer

Britannica.com: Encyclopedia article about thermometer

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