The Collaborative International Dictionary of English v.0.48:

Mellitic \Mel*lit"ic\, a. [Cf. F. mellitique. See Mellite.]
   (Chem.)
   (a) Containing saccharine matter; marked by saccharine
       secretions; as, mellitic diabetes.
   (b) Pertaining to, or derived from, the mineral mellite.
       [1913 Webster]

   Mellitic acid (Chem.), a white, crystalline, organic
      substance, C6(CO2H)6, occurring naturally in combination
      with aluminium in the mineral mellite, and produced
      artificially by the oxidation of coal, graphite, etc., and
      hence called also graphitic acid.
      [1913 Webster]