An Etymological Dictionary of Astronomy and Astrophysics

The physical constant, noted by k, relating the mean → kinetic energy of → molecules in an → ideal gas to their → absolute temperature. It is given by the ratio of the → gas constant to → Avogadro’s number.
Its value is about 1.380 x 10^-16erg K^-1.

See also: Named after the Austrian physicist Ludwig Boltzmann (1844-1906), who made important contributions to the theory of statistical mechanics; → constant.