# Definition:Kelvin

## Definition

The kelvin is the SI base unit of absolute temperature.

Its two reference points are:

$0 \ \mathrm K$, which is set at absolute zero, the temperature at which all thermal motion stops
$273 \cdotp 16 \ \mathrm K$, which is set at the triple point of water.

### Symbol

$\mathrm K$

The symbol for the kelvin is $\mathrm K$.

Note that, unlike the symbols for other temperature scales, there is no degree symbol used here: ${}^\circ \mathrm K$ is technically incorrect.

Its $\LaTeX$ code is \mathrm K .

## Source of Name

This entry was named for Lord Kelvin.