Col`u*mel"la (?), n. [L., dim. of
columen column. See Column.] 1.
(Bot.) (a) 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.
(b)A columnlike axis in the capsules of
2. (Anat.) 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.
3. (Zoöl.) (a)
The upright pillar in the axis of most univalve
shells. (b) The central pillar or axis
of the calicles of certain corals.