An absolute temperature scale used primarily in scientific specifications, devised by British physicist William Thomson, Lord Kelvin. On the Kelvin scale, absolute zero (the point at which all molecular motion has effectively ceased, -273.16oC and -459.69oF) is 0 K. The temperature intervals are exactly the same as those of the Celsius temperature scale, only 273.16 degrees greater. Thus, on the Kelvin scale, the freezing point of water (0oC and 32oF) is 273.16 K, while the boiling point of water (100oC and 212oF) is 373.16 K.
The Kelvin scale is also used to measure the color of a light source, by means of determining the temperature to which a black object would need to be heated in order to produce light of a certain wavelength or color. (See Color Temperature.) Kelvin is abbreviated K and does not take the degree sign (o).