circle of Willis

noun
circle of Wil·​lis | \ -ˈwil-əs How to pronounce circle of Willis (audio) \

Medical Definition of circle of Willis

: a complete ring of arteries at the base of the brain that is formed by the cerebral and communicating arteries and is a site of aneurysms

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Cite this Entry

“Circle of Willis.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/circle%20of%20Willis. Accessed 29 Oct. 2020.

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