Source : Webster's Revised Unabridged Dictionary (1913)

Coumaric \Cou*mar"ic\ (k??-m?r"?k), a.
   Relating to, derived from, or like, the {Dipterix odorata}, a
   tree of Guiana.

   {Coumaric acid} (Chem.), one of a series of aromatic acids,
      related to cinnamic acid, the most important of which is a
      white crystalline substance, {HO.C6H4.C2H2.CO2H}, obtained
      from the tonka bean, sweet clover, etc., and also produced
      artificially.