ENGLISH
REFERENCE

kelvin

n. countable
C1 Advanced US //ˈkɛɫvən// UK //kˈɛlvɪn// kelvin

n. the basic unit for measuring temperature in science. It starts at absolute zero, which is the coldest temperature possible.

n. the base unit of thermodynamic temperature in the International System of Units (SI). Equal in magnitude to the degree Celsius, but with its zero point at absolute zero.


SIMPLE

Water freezes at about 273 kelvins.

CONTEXTUAL

The laboratory equipment must be kept at a temperature of exactly four kelvins for the experiment to work.

COMPLEX

While the Celsius scale is used for daily weather, physicists prefer the kelvin because it provides an absolute measurement where zero represents the total absence of thermal energy.

Origin

Of Celtic/Scottish Gaelic origin, possibly from caol (“narrow”) or coille (“wooded”) + abhainn (“river”). The surname is derived from the river. The surname was also possibly influenced by Calvert (Middle English calfhirde).

Usage

When used as a unit, the word is not capitalized; however, the symbol 'K' is always uppercase. Unlike Celsius or Fahrenheit, it is not used with the word 'degree' or the degree symbol.

Pitfall

The temperature is 300 degrees Kelvin.The temperature is 300 kelvins.In the SI system, kelvin is an absolute unit and should not be preceded by the word 'degree' or the degree symbol.

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