commissure

noun

com·​mis·​sure ˈkä-mə-ˌshu̇r How to pronounce commissure (audio)
1
: a point or line of union or junction especially between two anatomical parts (such as adjacent heart valves)
2
: a connecting band of nerve tissue in the brain or spinal cord
commissural
ˌkä-mə-ˈshu̇r-əl How to pronounce commissure (audio)
adjective

Examples of commissure in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The anterior commissure is a tract connecting the two hemispheres (halves) of the brain. — New Atlas, 3 Aug. 2025

Word History

Etymology

Middle English, "suture, seam," borrowed from Middle French & Latin; Middle French, borrowed from Latin commissūra "joint, juncture, seam," from commissus (past participle of committere "to join together") + -ūra -ure — more at commit

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of commissure was in the 15th century

Rhymes for commissure

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Browse Nearby Words

commissural
commissure
commit
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Cite this Entry

“Commissure.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/commissure. Accessed 7 Jul. 2026.

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Medical Definition

commissure

noun
com·​mis·​sure ˈkäm-ə-ˌshu̇(ə)r How to pronounce commissure (audio)
1
: a point or line of union or junction between two anatomical parts (as the lips at their angles or adjacent heart valves)
2
: a connecting band of nerve tissue in the brain or spinal cord see anterior commissure, corpus callosum, gray commissure, habenular commissure, hippocampal commissure, posterior commissure compare massa intermedia
commissural
ˌkäm-ə-ˈshu̇r-əl How to pronounce commissure (audio)
adjective

More from Merriam-Webster on commissure

Britannica.com: Encyclopedia article about commissure

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