kelvin

1 of 2

noun

kel·​vin ˈkel-vən 

plural kelvins

: 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

2 of 2

adjective

: 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

Examples of kelvin in a Sentence

Recent Examples on the Web

Noun

At the temperatures of our experiments, three kelvins up to 10 kelvins, this material is very much in the strange metal regime. —Douglas Natelson, Scientific American, 19 Mar. 2024

Among these was cooling conventional silicon DRAM down to 77 kelvins and designing a glass bridge between the 77-K section and the main superconducting section, which operates at 4 K, with thin wires that allowed communication without thermal mixing. —Anna Herr, IEEE Spectrum, 15 May 2024

In general, the range from warmest to coolest is warm white (2,700 kelvins and below), soft white (2,700–3,000 kelvins), bright or cool white (3,500–5,000 kelvins), and daylight (5,000-plus kelvins). —Kat De Naoum, Better Homes & Gardens, 2 Jan. 2024

The material in the accretion disk is about a million kelvins, but the corona is a billion kelvins. —Michael Greshko, Quanta Magazine, 12 Feb. 2024

Word History

Etymology

Adjective

William Thomson, Lord Kelvin

First Known Use

Noun

1968, in the meaning defined above

Adjective

1908, in the meaning defined above

Kids Definition

kelvin

1 of 2 noun

kel·​vin ˈkel-vən 

: a unit of temperature equal to 1/273.16 of the Kelvin scale temperature of the triple point of water

Kelvin

2 of 2 adjective

: relating to or having a temperature scale on which the unit of measurement is the same size as the Celsius degree and according to which absolute zero is 0 K (-273.15°C)

—abbreviation K

Etymology

Adjective

named for William Thomson, Lord Kelvin (1824–1907), British mathematician and physicist

Medical Definition

kelvin

1 of 2 noun

kel·​vin ˈkel-vən 

: 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

2 of 2 adjective

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

Biographical Definition

Kelvin

biographical name

Kel·​vin ˈkel-vən 

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