Source : Webster's Revised Unabridged Dictionary (1913)

Infundibulum \In`fun*dib"u*lum\, n.; pl. L. {Infundibula}, E.
   {Infundibulums}. [L., a funnel, from infundere to pour in or
   into. See {Infuse}.]
   1. (Anat.) A funnel-shaped or dilated organ or part; as, the
      infundibulum of the brain, a hollow, conical process,
      connecting the floor of the third ventricle with the
      pituitary body; the infundibula of the lungs, the enlarged
      terminations of the bronchial tubes.

   2. (Zo["o]l.)
      (a) A central cavity in the Ctenophora, into which the
          gastric sac leads.
      (b) The siphon of Cephalopoda. See {Cephalopoda}.

Source : WordNet®

infundibulum
     n : any of various funnel-shaped parts of the body (but
         especially the hypophyseal stalk)
     [also: {infundibula} (pl)]