a. [ L. ferrum iron: cf. F. ferrique. See Ferrous. ] Pertaining to, derived from, or containing iron. Specifically (Chem.), denoting those compounds in which iron has a higher valence than in the ferrous compounds; as, ferric oxide; ferric acid. [ 1913 Webster ]

Ferric acid (Chem.), an acid, H2FeO4, which is not known in the free state, but forms definite salts, analogous to the chromates and sulphates. --
Ferric oxide (Chem.), sesquioxide of iron, Fe2O3; hematite. See Hematite. [ 1913 Webster ]

n. [ Ferri- + cyanate. ] (Chem.) A salt of ferricyanic acid; a ferricyanide. [ 1913 Webster ]

a. [ Ferri- + cyanic. ] (Chem.) Pertaining to, or derived from, a ferricyanide. [ 1913 Webster ]

Ferricyanic acid (Chem.), a brown crystalline substance, H6(CN)12Fe2, obtained from potassium ferricyanide, and regarded as the type of the ferricyanides; -- called also hydro-ferricyanic acid, hydrogen ferricyanide, etc. [ 1913 Webster ]

n. [ Ferri- + cyanide. ] (Chem.) One of a complex series of double cyanides of ferric iron and some other base. [ 1913 Webster ]

Potassium ferricyanide (Chem.), red prussiate of potash; a dark, red, crystalline salt, K6(CN)12Fe2, consisting of the double cyanide of potassium and ferric iron. From it is derived the ferrous ferricyanate, Turnbull's blue. [ 1913 Webster ]