Euchroic

Eu*chro"ic (?), a. [Gr. ? well- colored; ? well + ? color.] (Chem.) Having a fine color.

Euchroic acid (Chem.), an organic, imide acid, obtained as a colorless crystalline substance, C₁₂H₄N₂O₈ by heating an ammonium salt of mellitic acid. By reduction it is changed to a dark blue substance (euchrone), -- hence its name.