Also found in: Thesaurus, Medical, Encyclopedia, Wikipedia.
A glacial or syrupy viscous liquid, H4P2O7, used as a catalyst and in organic chemical manufacture.
(Elements & Compounds) a crystalline soluble solid acid formed by the reaction between one molecule of phosphorus pentoxide and two water molecules. Formula: H4P2O7. See also polyphosphoric acid
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
py′ro•phos•phor′ic ac′id(ˈpaɪ roʊ fɒsˈfɔr ɪk, -ˈfɒr-, ˌpaɪ-)
a crystalline, water-soluble powder, H4P2O7, used as a catalyst.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.