- 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. - A central cavity in the Ctenophora, into which the
gastric sac leads. - The siphon of Cephalopoda. See Cephalopoda.