\Prus"sian\, a. [From Prussia, the country: cf. F.
prussien.]
Of or pertaining to Prussia. -- n. A native or inhabitant of
Prussia.
{Prussian blue} (Chem.), any one of several complex double
   cyanides of ferrous and ferric iron; specifically, a dark
   blue amorphous substance having a coppery luster, obtained
   by adding a solution of potassium ferrocyanide (yellow
   prussiate of potash) to a ferric salt. It is used in
   dyeing, in ink, etc. Called also {Williamson's blue},
   {insoluble Prussian blue}, {Berlin blue}, etc.
{Prussian carp} (Zo["o]l.) See {Gibel}.
{Prussian green}. (Chem.) Same as {Berlin green}, under
   {Berlin}.