- n hypophosphorous acid a clear or yellow monobasic acid (H3PO2)
Webster's Revised Unabridged Dictionary
- Hypophosphorous acid (Chem) , an acid, H3PO2, whose salts are produced by the action of barium hygrate on phosphorus. It may be obtained from its water solution, by exaporation and freezing, as a white crystalline substance. It is a powerful reducing agent.