Prussian blue noun 2adjective 1forms 3 noun2 •An insoluble dark, bright blue pigment, ferric ferrocyanide (equivalent to ferrous ferricyanide), used in painting and dyeing, and as an antidote for certain kinds of heavy metal poisoning.It is well known that Davy doubted the elementary character of iodine and Mr. Reade's soluble Prussian blue gives us some reason to believe that the great chemist may be correct. — 1847 •A moderate to rich blue colour, tinted with deep greenish blue. adjective1 •Of a rich blue colour, tinted with green. formsPrussian blues · more Prussian blue · most Prussian blue
