The Collaborative International Dictionary
Polysilicic acid
Polysilicic \Pol`y*si*lic"ic\, a. [Poly- + silicic.] (Chem.) Of or pertaining to compounds formed by the condensation of two or more molecules of silicic acid.
Polysilicic acid (Chem.), any one of a series of acids formed by the condensation of two or more molecules of silicic acid, with elimination of water.
Wiktionary
polysilicic acid
n. (context obsolete chemistry English) Any of a series of condensation products of silicic acid