noun Chemistry. a compound that in the form of its normal salt, Al(C2H3O2)3, obtained as a white, water-soluble, amorphous powder, is used chiefly in medicine as an astringent and as an antiseptic, and in the form of its basic salt, Al(C2H3O2)2OH, obtained as a white, crystalline, water-insoluble powder, is used chiefly in the textile industry as a waterproofing agent, as a fireproofing agent, and as a mordant.
