What is the meaning of Septum?

A wall separating two cavities; a partition.

Ellipsis of nasal septum (“the cartilaginous center wall of the nose separating the two nostrils”).

Either of the two walls that separate the atria or ventricles of the heart into left and right chambers.

A partition that separates the cells of a fruit.

A partition that separates the cells of a (septated) fungus.

One of the radial calcareous plates of a coral.

One of the transverse partitions dividing the shell of a mollusk, or of a rhizopod, into several chambers.

One of the transverse partitions dividing the body cavity of an annelid.

One of the walls dividing two holes in a parallel-hole collimator

Ellipsis of septum ring or septum piercing.

septum

alternative form of saeptum

septum (septum ring or septum piercing)

Source: wiktionary.org