(Science: chemistry) Aerated salt; a white crystalline substance having an alkaline taste and reaction, consisting of sodium bicarbonate (see under Sodium) It is lagerly used in cooking, with sour milk (lactic acid) or cream of tartar as a substitute for yeast. It is also an ingridient of most baking powders, and is used in the preparation of effervescing drinks.
Origin: NL. Sal aeratus; so called because it is a source of fixed air (carbon dioxide). See Sal, and and Aerated.