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triphosphoric acid

American  
[trahy-fos-fawr-ik, -for-, trahy-] / ˈtraɪ fɒsˈfɔr ɪk, -ˈfɒr-, ˌtraɪ- /

noun

Chemistry.
  1. the hypothetical acid H 5 P 3 O 10 , known chiefly by its salts.


Etymology

Origin of triphosphoric acid

tri- + phosphoric acid