Definition of sodium silicate
: any of various water-soluble substances obtained in the form of crystals, glasses, powders, or aqueous solutions usually by melting silica with a sodium compound (such as sodium carbonate or sodium hydroxide): such as
a
or
sodium orthosilicate
: a corrosive crystalline substance regarded as a salt Na4SiO4 or 2Na2O.SiO2 of orthosilicic acid or as a mixture of sodium metasilicate with sodium hydroxide and used chiefly in heavy-duty cleaning compositions
b
or
sodium metasilicate
: a crystalline salt Na2SiO3 or Na2O.SiO2 either in the anhydrous or hydrated form used chiefly as a detergent
c
or
sodium sesquisilicate
: a corrosive crystalline salt regarded as intermediate in composition between sodium orthosilicate and sodium metasilicate and used in heavy-duty cleaning compositions
—not used systematically
d
: water glass
