from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Excessive or abnormal thickening or growth of bone tissue.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. An excessive growth or thickening of bone

from The Century Dictionary and Cyclopedia

  • n. A morbid outgrowth of bone from a bone.
  • n. An overgrowth of bone; a normal (not morbid) exostosis or increase of bony tissue.


hyper- + ost(eo)- + -osis.
(American Heritage® Dictionary of the English Language, Fourth Edition)


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