Prussian

Chamber's Twientieth Century Dictionary · 1908 · p. 82

prush′an, adj. of or pertaining to Pru ia .— n. an inhabitant of Pru ia.— v.t. Pru ′ianise .— n. Pru ′iate , a salt of pru ic acid: a cyanide.— adj. Pru ′ic , pertaining to Pru ian blue.— Pru ian blue , cyanide of pota ium and iron; Pru ic acid , a deadly poison, an acid first obtained from Pru ian blue—also Hydrocyanic acid .