sodium bisulfate
noun
variants:
or less commonly sodium acid sulfate
Definition of sodium bisulfate
: a crystalline salt NaHSO4 that gives an acid reaction in solution, that is usually made by the reaction of sulfuric acid with common salt or sodium sulfate, and that is used chiefly as a flux in pickling metals and as an acid ingredient in dyeing and cleaning compositions; sodium hydrogen sulfate
— called also niter cake