What does commissure mean?
A commissure is a point or band where two parts of the body join together. The term is used most often in anatomy and neuroscience, where it refers specifically to bundles of nerve fibres that connect corresponding regions on opposite sides of the brain or spinal cord. The best-known example is the corpus callosum, the massive commissure linking the brain's two hemispheres and allowing them to communicate. Beyond neuroanatomy, the word also describes other natural junctions, such as the corners where the eyelids or lips meet. Because it is precise and technical, 'commissure' appears mainly in medical textbooks, research papers, and clinical discussion rather than casual speech. It carries no emotional connotation; its value lies in exactness. Derived from Latin roots meaning 'a joining together', it shares ancestry with words like 'mission' and 'transmit', which also stem from the Latin verb meaning to send. For students of medicine, psychology, or biology, it is an essential term for describing how paired structures are functionally united.
nounA place where two parts of the body, especially nervous tissue, join or come together; in anatomy, a band of nerve fibres connecting corresponding parts of the brain or spinal cord.
- A band of nerve fibres connecting corresponding regions of the brain or spinal cord.
- More generally, any anatomical site where two parts or structures of the body join or meet.
"The corpus callosum is the largest commissure of the human brain."
"Damage to the anterior commissure can disrupt communication between the brain's hemispheres."
"The surgeon carefully examined the commissure where the eyelids meet."
Regular plural; used when discussing multiple junctions or fibre tracts.
"The brain contains several smaller commissures besides the corpus callosum."
The largest commissure in your brain — the corpus callosum — contains roughly 200 million nerve fibres stitching your two hemispheres together.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of commissure
The word derives from Latin 'commissura', meaning 'a joining together', formed from 'com-' ('together') plus 'mittere' ('to send' or 'put'), the same root behind 'commit', 'mission', and 'transmit'. It entered English in the early 15th century via medical Latin, initially describing general anatomical junctions before acquiring its specialised sense for nerve-fibre tracts as neuroanatomy developed. Cognates appear across Romance languages, including French 'commissure' and Italian 'commissura'.
Related word forms
How commissure is actually used
Primarily a technical term used in anatomy, neuroanatomy, and medical writing; rare in everyday conversation. Plural is 'commissures'.
Easily confused with commissure
A commissary is a store or officer supplying food and provisions, while a commissure is an anatomical junction where two body parts meet.