kelvin

noun
kel·​vin | \ ˈkel-vən How to pronounce kelvin (audio) \
plural kelvins

Definition of kelvin

 (Entry 1 of 3)

: the base unit of temperature in the International System of Units that is defined by setting the fixed numerical value of the Boltzmann constant to be 1.380649 x 10–23 joules per kelvin and that is equal to 1/273.16 of the Kelvin scale temperature of the triple point of water abbreviation K

Kelvin

adjective

Definition of Kelvin (Entry 2 of 3)

: relating to, conforming to, or having a thermometric scale on which the unit of measurement equals the Celsius degree and according to which absolute zero is 0 K, the equivalent of −273.15°C

Kelvin

biographical name
Kel·​vin | \ ˈkel-vən How to pronounce Kelvin (audio) \

Definition of Kelvin (Entry 3 of 3)

1st Baron 1824–1907 William Thomson British mathematician and physicist

Examples of kelvin in a Sentence

Adjective a temperature of 200 degrees Kelvin
Recent Examples on the Web: Noun Aspelmeyer’s group says that the spread in their particle’s position is only 1.3 times that of the zero-point motion, equivalent to a temperature of just a few millionths of a kelvin above absolute zero. Quanta Magazine, 18 Aug. 2021 Inside the sun, where nuclear fusion occurs, temperatures can swell to 15 million kelvin. Jennifer Leman, Popular Mechanics, 25 Sep. 2020 At night, the surface of even the closest planet to the sun, Mercury, drops to about 95 kelvin. Jennifer Leman, Popular Mechanics, 25 Sep. 2020 Pluto’s surface temperature reaches about 40 kelvin. Jennifer Leman, Popular Mechanics, 25 Sep. 2020 Color temperature addresses a unit of measurement called degrees kelvin. Popular Science, 15 Apr. 2020 Brief pulses heated the carbon to more than 3000 kelvins (about 2700°C), snapping the bonds between carbon atoms. Robert F. Service, Science | AAAS, 27 Jan. 2020 But Spitzer used passive methods—reflective materials and radiators to shed heat into space—to cool most of the spacecraft to 40 kelvins. Daniel Clery, Science | AAAS, 23 Jan. 2020 Pluto’s surface temperature reaches about 40 degrees kelvin. Jennifer Leman, Popular Mechanics, 22 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'kelvin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of kelvin

Noun

1968, in the meaning defined above

Adjective

1908, in the meaning defined above

History and Etymology for kelvin

Adjective

William Thomson, Lord Kelvin

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Cite this Entry

“Kelvin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/kelvin. Accessed 27 Nov. 2021.

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More Definitions for kelvin

Kelvin

adjective

English Language Learners Definition of Kelvin

: relating to or having a scale for measuring temperature on which the boiling point of water is at 373.1 degrees above zero and the freezing point is at 273.15 degrees above zero

kelvin

noun
kel·​vin | \ ˈkel-vən How to pronounce kelvin (audio) \

Medical Definition of kelvin

 (Entry 1 of 2)

: the base unit of temperature in the International System of Units that is equal to 1/273.16 of the Kelvin scale temperature of the triple point of water and also to the Celsius degree

Kelvin

adjective

Medical Definition of Kelvin (Entry 2 of 2)

: relating to, conforming to, or being the Kelvin scale

More from Merriam-Webster on kelvin

Britannica English: Translation of kelvin for Arabic Speakers

Britannica.com: Encyclopedia article about kelvin

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