sodium bicarbonate \sodium bicarbonate\,
   a white crystalline substance, hnaco3, with a slight
   alkaline taste resembling that of sodium carbonate. it is
   found in many mineral springs and also produced
   artificially,. it is used in cookery, in baking powders, and
   as a source of carbonic acid gas carbon dioxide for soda
   water. called also baking soda, cooking soda,
   bicarbonate of soda, bicarb, saleratus, and
   technically, acid sodium carbonate, sodium acid
   carbonate, primary sodium carbonate, sodium dicarbonate,
   etc.
   1913 webster
see also:
hnaco3 baking soda cooking soda bicarbonate of soda bicarb saleratus 
acid sodium carbonate sodium acid carbonate primary sodium carbonate sodium dicarbonate