Toluic \To*lu"ic\, a. (Chem.) Pertaining to, or designating, one of three metameric acids, {CH3.C6H4.CO2H}, which are related to toluene and analogous to benzoic acids. They are white crystalline substances, and are called respectively {orthotoluic} acid, {metatoluic} acid, and {paratoluic} acid. [1913 Webster]