foramen magnum

noun

fo·​ra·​men mag·​num fə-ˌrā-mən-ˈmag-nəm How to pronounce foramen magnum (audio)
: the opening in the skull through which the spinal cord passes to become the medulla oblongata

Examples of foramen magnum 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.
Chiari malformation type 1 is a rare brain condition where the cerebellum, a brain area responsible for balance and posture, droops down slightly through a small hole in the skull called the foramen magnum. — Ruairi MacKenzie, Discover Magazine, 16 July 2025 Though the fossil exhibited apelike features, the position of the foramen magnum, or the opening that allows the spinal cord and brain to meet, convinced Dart that the child had walked upright like a human. — Smithsonian, 27 Mar. 2017 For example, the location of the foramen magnum, the opening in the skull for the spinal cord, reveals whether its possessor orients horizontally or vertically. — David P. Barash, WSJ, 16 June 2021

Word History

Etymology

New Latin, literally, large opening

First Known Use

1857, in the meaning defined above

Time Traveler
The first known use of foramen magnum was in 1857

Browse Nearby Words

foramen
foramen magnum
foramen ovale
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Cite this Entry

“Foramen magnum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/foramen%20magnum. Accessed 8 Jul. 2026.

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Kids Definition

foramen magnum

noun
fo·​ra·​men mag·​num fə-ˌrā-mən-ˈmag-nəm How to pronounce foramen magnum (audio)
: the opening in the skull through which the spinal cord joins the brain

Medical Definition

foramen magnum

noun
foramen mag·​num -ˈmag-nəm How to pronounce foramen magnum (audio)
: the opening in the skull through which the spinal cord passes to become the medulla oblongata

More from Merriam-Webster on foramen magnum

Britannica.com: Encyclopedia article about foramen magnum

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