Septum
Septum , noun
[Latin septum, saeptum, an inclosure, hedge, fence, from sepire, saepire, to hedge in, inclose.]
1.
A wall separating two cavities; a partition; as, the nasal septum.
2.
(Botany) A partition that separates the cells of a fruit.
3.
(a) (Zoology) One of the radial calcareous plates of a coral.
(b)
(Zoology) One of the transverse partitions dividing the shell of a mollusk, or of a rhizopod, into several chambers.
(c)
(Zoology) One of the transverse partitions dividing the body cavity of an annelid.