The Collaborative International Dictionary of English v.0.48:

Facet \Fac"et\, n. [F. facette, dim. of face face. See Face.]
   1. A little face; a small, plane surface; as, the facets of a
      diamond. [Written also facette.]
      [1913 Webster]

   2. (Anat.) A smooth circumscribed surface; as, the articular
      facet of a bone.
      [1913 Webster]

   3. (Arch.) The narrow plane surface between flutings of a
      column.
      [1913 Webster]

   4. (Zool.) One of the numerous small eyes which make up the
      compound eyes of insects and crustaceans.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Facet \Fac"et\, v. t. [imp. & p. p. Faceted; p. pr. & vb. n.
   Faceting.]
   To cut facets or small faces upon; as, to facet a diamond.
   [1913 Webster]

WordNet (r) 3.0 (2006):

facet
    n 1: a distinct feature or element in a problem; "he studied
         every facet of the question" [syn: aspect, facet]
    2: a smooth surface (as of a bone or cut gemstone)