1. (Science: anatomy) 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. (Science: botany) The throat of a calyx, corolla, etc.
3. (Science: zoology) That portion of the interior of a spiral shell which can be seen by looking into the aperture.