annulus fibrosus

noun
annulus fi·​bro·​sus | \ -fī-ˈbrō-səs, -fi- How to pronounce annulus fibrosus (audio) \
variants: also anulus fibrosus \ ˈan-​yə-​ləs-​ How to pronounce annulus fibrosus (audio) \

Medical Definition of annulus fibrosus

: a ring of fibrous tissue (such as that surrounding a heart valve) especially : the outer portion of an intervertebral disk that surrounds the nucleus pulposus and is composed chiefly of layers of collagen fibers Disks between the vertebrae have a soft center—a nucleus pulposus—and a tougher exterior, annulus fibrosus. — Matthew Sturdevant, The Hartford (Connecticut) Courant, 30 May 2010 The nucleus pulposus can bulge out or herniate the anulus fibrosus, but the disk itself does not "slip." — John Palo, Newsday, 21 Feb. 1990

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Cite this Entry

“Annulus fibrosus.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/annulus%20fibrosus. Accessed 27 Jan. 2021.

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