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pyrosulfuric

American  
[pahy-roh-suhl-fyoor-ik] / ˌpaɪ roʊ sʌlˈfyʊər ɪk /
Or pyrosulphuric

adjective

Chemistry.
  1. of or derived from pyrosulfuric acid; disulfuric.


Etymology

Origin of pyrosulfuric

First recorded in 1870–75; pyro- + sulfuric