The Collaborative International Dictionary of English v.0.48:

Caffeic \Caf*fe"ic\, a. [See Coffee.] (Chem.)
   Pertaining to, or obtained from, coffee.
   [1913 Webster]

   Caffeic acid, an acid obtained from coffee tannin, as a
      yellow crystalline substance, C9H8O4.
      [1913 Webster] caffein