teraconic

from The Century Dictionary.

• Noting an acid, a colorless compound, HOCOC(CH₂COOH):C(CH₃)₂, prepared by the action of sodium on ethyl terebate. It forms lustrous prisms or large triclinic crystals, and melts and decomposes at 161–163°C.

from the GNU version of the Collaborative International Dictionary of English.

• adjective (Chem.) Pertaining to, or designating, an acid obtained by the distillation of terebic acid, and homologous with citraconic acid.