“+...- noun
Etymology: silic- + tungstic
: any of several heteropoly acids of silicon and tungsten ; especially : a pale-yellow crystalline acid H 4 SiW 12 O 40 . x H 2 O containing 12 atoms of tungsten in the molecule, obtainable by acid hydrolysis of a mixture of sodium tungstate and sodium silicate, and used chiefly as a precipitant for alkaloids — called also tungstosilicic acid