sodium

Etymology

Coined by British chemist Humphry Davy in 1808, from soda + -ium.

noun

1. The chemical element (symbol Na) with an atomic number of 11 and atomic weight of 22.990. It is a soft, waxy, silvery, reactive alkali metal that is never found unbound in nature.
2. (attributive) Employing sodium.
   From Keighley onwards we had obviously returned to civilisation, for the surrounding country was now studded with the sodium street lights of suburbia and a thickening industrial haze was blotting out the moon. 1960 January, G. Freeman Allen, “"Condor"—British Railways' fastest freight train”, in Trains Illustrated, page 48