tartronic

from The Century Dictionary.

• Noting an acid, a colorless compound, HOCOCH(OH)COOH.1/2H₂O, prepared by the reduction of mesoxalic acid. It crystallizes in prisms, when anhydrous sublimes at 110–120° C., and melts and decomposes at 185–187° C. Also called hydroxymalonic acid.

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

• adjective (Chem.) Of, pertaining to, or designating, an organic acid (called also hydroxy malonic acid) obtained, by reducing mesoxalic acid, as a white crystalline substance.