syn·​os·​to·​sis | \ ˌsi-ˌnä-ˈstō-səs How to pronounce synostosis (audio) \
plural synostoses\ ˌsi-​ˌnä-​ˈstō-​ˌsēz How to pronounce synostoses (audio) \

Definition of synostosis

: union of two or more separate bones to form a single bone

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Examples of synostosis in a Sentence

Recent Examples on the Web Aist was born with congenital radioulnar synostosis, a condition leading to the abnormal connection of the bones in the forearm, the radius and ulna, according to the National Institutes of Health. Greeley Tribune, The Denver Post, "“It’s exhilarating”: Prosthetic helps Greeley student pilot fly pain-free," 19 July 2020

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

First Known Use of synostosis

circa 1848, in the meaning defined above

History and Etymology for synostosis

syn- + -ostosis

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Time Traveler for synostosis

Time Traveler

The first known use of synostosis was circa 1848

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Statistics for synostosis

Cite this Entry

“Synostosis.” Dictionary, Merriam-Webster, Accessed 28 Nov. 2020.

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More Definitions for synostosis


syn·​os·​to·​sis | \ ˌsin-ˌäs-ˈtō-səs How to pronounce synostosis (audio) \
plural synostoses\ -​ˌsēz How to pronounce synostoses (audio) \

Medical Definition of synostosis

: union of two or more separate bones to form a single bone also : the union so formed (as at an epiphyseal line)

Other Words from synostosis

synostotic \ -​ˈtät-​ik How to pronounce synostotic (audio) \ adjective
synostotically \ -​i-​k(ə-​)lē How to pronounce synostotically (audio) \ adverb

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