Commissure

A commissure is the place where two things are joined. The term is used especially in the fields of anatomy and biology.

In anatomy, commissure refers to a bundle of nerve fibers that cross the midline at their level of origin or entry (as opposed to a decussation of fibers that cross obliquely).

In biology, the meeting of the two valves of a brachiopod or clam is a commissure; in botany, the term is used to denote the place where a fern's laterally expanded vein endings come together in a continuous marginal sorus.

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