Septum

In biology, a septum (Latin for something that encloses; plural septa) is a wall, dividing a cavity or structure into smaller ones.

Histological septa are seen throughout most tissues of the body, particularly where they are needed to stiffen soft cellular tissue, and they also provide planes of ingress for small blood vessels. Because the dense collagen fibres of a septum usually extend out into the softer adjacent tissues, microscopic fibrous septa are less clearly defined than the macroscopic types of septa listed above. In rare instances, a septum is a cross-wall. Thus it divides a structure into smaller parts.

The Septum (cell biology) is the boundary formed between dividing cells in the course of cell division.

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