The Collaborative International Dictionary of English v.0.48:

Paten \Pat"en\, n. [LL. patina, patena, fr. L. patina, patena, a
   pan; cf. L. patere to be open, E. patent, and Gr. pata`nh a
   kind of flat dish: cf. F. pat[`e]ne. Cf. Patina.]
   1. A plate. [Obs.]
      [1913 Webster]

   2. (Eccl.) The place on which the consecrated bread is placed
      in the Eucharist, or on which the host is placed during
      the Mass. It is usually small, and formed as to fit the
      chalice, or cup, as a cover.
      [1913 Webster] [Written also patin, patine.]
      [1913 Webster]