%septum%

‖n.; pl. Septa [ L. septum, saeptum, an inclosure, hedge, fence, fr. sepire, saepire, to hedge in, inclose. ] 1. A wall separating two cavities; a partition; as, the nasal septum. [ 1913 Webster ]

2. (Bot.) A partition that separates the cells of a fruit. [ 1913 Webster ]

3. (Zool.) (a) One of the radial calcareous plates of a coral. (b) One of the transverse partitions dividing the shell of a mollusk, or of a rhizopod, into several chambers. See Illust. under Nautilus. (c) One of the transverse partitions dividing the body cavity of an annelid. [ 1913 Webster ]