ex·​os·​to·​sis | \ ˌek-(ˌ)sä-ˈstō-səs How to pronounce exostosis (audio) \
plural exostoses\ ˌek-​(ˌ)sä-​ˈstō-​ˌsēz How to pronounce exostosis (audio) \

Definition of exostosis

: a spur or bony outgrowth from a bone or the root of a tooth

Examples of exostosis in a Sentence

Recent Examples on the Web The dense growths are known as external auditory exostoses. Ashley Strickland, CNN, 14 Aug. 2019 Cold Water Love catching waves? Surfers and other cold water swimmers are prone to something called exostoses, or small bony growths in the ear canal that develop slowly over time and can prevent sound from getting in. Clare Thorp, Cosmopolitan, 2 Aug. 2017 Riley was born with a genetic condition called hereditary multiple exostoses (HME), which causes irregular bone growth. George Diaz, OrlandoSentinel.com, 4 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'exostosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of exostosis

1736, in the meaning defined above

History and Etymology for exostosis

New Latin, from Greek exostōsis, from ex out of + osteon bone — more at ex-, osseous

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The first known use of exostosis was in 1736

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Cite this Entry

“Exostosis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/exostosis. Accessed 24 Jan. 2022.

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More Definitions for exostosis


ex·​os·​to·​sis | \ ˌek-(ˌ)säs-ˈtō-səs How to pronounce exostosis (audio) \
plural exostoses\ -​ˌsēz How to pronounce exostosis (audio) \

Medical Definition of exostosis

: a spur or bony outgrowth from a bone or the root of a tooth

Other Words from exostosis

exostotic \ -​ˈtät-​ik How to pronounce exostosis (audio) \ adjective

More from Merriam-Webster on exostosis

Britannica.com: Encyclopedia article about exostosis


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