[ek-so-stoh-sis, -suh-]
noun, plural exostoses [ek-so-stoh-seez, -suh-] . Pathology.
the abnormal formation of a bony growth on a bone or tooth.

1730–40; < Neo-Latin < Greek exóstōsis an outgrowth. See ex-3, ostosis

exostosed, adjective
exostotic [ek-so-stot-ik, -suh-] , adjective
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World English Dictionary
exostosis (ˌɛksɒˈstəʊsɪs)
n , pl -ses
an abnormal bony outgrowth from the surface of a bone
[C18: via New Latin from Greek, from ex-1 + osteon bone]

Collins English Dictionary - Complete & Unabridged 10th Edition
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American Heritage
Medical Dictionary

exostosis ex·os·to·sis (ěk'sŏ-stō'sĭs)
n. pl. -ses (-sēz)
A projection that is capped by cartilage and arises from a bone that develops from cartilage. Also called hyperostosis, poroma.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Encyclopedia Britannica


solitary benign tumour that consists partly of cartilage and partly of bone. Osteochondromas are common and may develop spontaneously following trauma or may have a hereditary basis. No treatment is required unless the tumour interferes with function, in which case it should be surgically removed. Rarely, a solitary osteochondroma will become malignant in adulthood, giving rise to a chondrosarcoma.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Look for an exostosis, a bony growth on the outside of the ear developed from diving, she says.
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