The Collaborative International Dictionary of English v.0.48:

Fauces \Fau"ces\, n. pl. [L.]
   1. (Anat.) The narrow passage from the mouth to the pharynx,
      situated between the soft palate and the base of the
      tongue; -- called also the isthmus of the fauces. On
      either side of the passage two membranous folds, called
      the pillars of the fauces, inclose the tonsils.
      [1913 Webster]

   2. (Bot.) The throat of a calyx, corolla, etc.
      [1913 Webster]

   3. (Zool.) That portion of the interior of a spiral shell
      which can be seen by looking into the aperture.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

faux \faux\ (f[add]ks), n.; pl. fauces (f[add]"s[=e]z). [L.]
   See Fauces.

WordNet (r) 3.0 (2006):

fauces
    n 1: the passage between the back of the mouth and the pharynx