D defs.my
Entry 1 sense Webster, 1913

Prussic

· Prus·sic · IPA
01 a. designating the acid now called hydrocyanic acid, but formerly called prussic acid, because Prussian blue is derived from it or its compoun…
  1. 1.
    designating the acid now called hydrocyanic acid, but formerly called prussic acid, because Prussian blue is derived from it or its compounds. See Hydrocyanic.(Old Chem.) See: Hydrocyanic