(1):
(n.) A columnlike axis in the capsules of mosses.
(2):
(n.) The upright pillar in the axis of most univalve shells.
(3):
(n.) The central pillar or axis of the calicles of certain corals.
(4):
(n.) An axis to which a carpel of a compound pistil may be attached, as in the case of the geranium; or which is left when a pod opens.
(5):
(n.) A term applied to various columnlike parts; as, the columella, or epipterygoid bone, in the skull of many lizards; the columella of the ear, the bony or cartilaginous rod connecting the tympanic membrane with the internal ear.