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hydrosulfurous

American  
[hahy-droh-suhl-fyoor-uhs, -druh-suhl-fer-uhs] / ˌhaɪ droʊ sʌlˈfyʊər əs, -drəˈsʌl fər əs /
Or hydrosulphurous

adjective

  1. hyposulfurous.


Etymology

Origin of hydrosulfurous

First recorded in 1850–55; hydro- 2 + sulfurous