Infundibulum

·noun The siphon of Cephalopoda. ·see Cephalopoda.

II. Infundibulum ·noun A central cavity in the Ctenophora, into which the gastric sac leads.

III. Infundibulum ·noun 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.