%isocyanic%

a. [ Iso- + cyanic. ] (Chem.) Designating an acid isomeric with cyanic acid. [ 1913 Webster ]

Isocyanic acid, an acid metameric with cyanic acid, and resembling it in its salts. It is obtained as a colorless, mobile, unstable liquid by the heating cyanuric acid. Called technically carbimide. [ 1913 Webster ]