Source : Webster's Revised Unabridged Dictionary (1913)

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.

   2. (Bot.) The throat of a calyx, corolla, etc.

   3. (Zo["o]l.) That portion of the interior of a spiral shell
      which can be seen by looking into the aperture.

Faux \Faux\, n.; pl. {Fauces}. [L.]
   See {Fauces}.

Source : WordNet®

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