heteropoly acid
nounDefinition of heteropoly acid
: any of a large group of complex oxygen-containing acids derived from two or more different inorganic acids by elimination of water from two or more molecules of the acids
especially
: an acid regarded as formed by combination of several molecules of an acid anhydride (as molybdenum trioxide or tungsten trioxide) with a second acid that furnishes the central atom (as phosphorus or silicon) of the complex
—distinguished from isopoly acid