- Also called monobasic sodium phosphate. a white, crystalline, slightly hygroscopic, water-soluble powder, NaH2PO4, used chiefly in dyeing and in electroplating.
- Also called dibasic sodium phosphate, disodium phosphate. a water-soluble compound that in its anhydrous form, Na2HPO4, occurring as a white, crystalline, hygroscopic powder, is used chiefly in the manufacture of ceramic glazes, enamels, baking powder, and cheeses, and that in its hydrated form, Na2HPO4⋅xH2O, occurring as clear colorless crystals, is used chiefly in the manufacture of dyes, fertilizers, detergents, and pharmaceuticals.
- Also called tribasic sodium phosphate, trisodium phosphate, TSP. a colorless water-soluble compound, Na3PO4⋅12H2O, occurring as crystals: used chiefly in the manufacture of water-softening agents, detergents, paper, and textiles.
- any sodium salt of any phosphoric acid, esp one of three salts of orthophosphoric acid having formulas NaH 2 PO 4 (monosodium dihydrogen orthophosphate), Na 2 HPO 4 (disodium monohydrogen orthophosphate), and Na 3 PO 4 (trisodium orthophosphate)