Chem.
a crystalline, water-insoluble powder, Al(OH) 3 or Al 2 O 3 ·3H 2 O, obtained chiefly from bauxite: used in the manufacture of glass, ceramics, and printing inks, in dyeing, and in medicine as an antacid and in the treatment of ulcers. Also called alumina trihydrate, aluminum hydrate, hydrated alumina .
[ 1870-75 ]