What is "sodium azide"

azide \az"ide\ n. (Chem.) any chemical compound containing the azido group -N3, such as sodium azide (ionic and inorganic) or ethyl azide (organic and nonionic).

n. (context chemistry English) a white, crystalline salt, NaN₃; it is explosive, and is used in automobile airbags

Sodium azide is the inorganic compound with the formula NaN. This colorless salt is the gas-forming component in many car airbag systems. It is used for the preparation of other azide compounds. It is an ionic substance, is highly soluble in water, and is very acutely toxic.