from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A large multinucleate cell found in growing bone that resorbs bony tissue, as in the formation of canals and cavities.
  • noun An instrument used in surgical osteoclasis.

from The Century Dictionary.

  • noun In surgery, an apparatus for fracturing bones in order to correct deformities.
  • noun A large multinucleated cell supposed to be concerned in the absorption of bone-tissue. Originally osteoklast (Kölliker). Also called giant cell, myeloplax, and myeloplaque.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Physiol.) Same as myeloplax, a large multinucleate cell within the bone, which functions in the absroption and removal of bone tissue.
  • noun An instrument for performing osteoclasis.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun physiology, cytology A large multinuclear cell associated with the resorption of bone
  • noun An instrument for performing osteoclasis.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun cell that functions in the breakdown and resorption of bone tissue


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

[osteo– + Medieval Latin -clastēs, breaker (from Late Greek -klastēs, from Greek klastos, broken, from klān, to break).]

from Wiktionary, Creative Commons Attribution/Share-Alike License

osteo- (“bone”) +‎ -clast (“break”)


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  • RANKL, also known as osteoclast differentiation factor (ODF), tumor necrosis factor - related activation-induced cytokine (TRANCE) and osteoprotegerin ligand, is a member of the TNF ligand family (106) produced in osteoblastic lineage cells and activated T cells

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  • Slide 26: (OPG), also known as osteoclast inhibitory factor (OCIF) is a soluble decoy receptor for RANKL (111).

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  • Skeleton Crew osteoclast The drugs target a protein called RANK Ligand, which helps regulate cells called osteoclasts that break down bone.

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  • Incidentally, osteoclast is a type of cell that attacks the bone.

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  • An osteoblast engaged in the absorption instead of the formation of bone is called an osteoclast.

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  • When interference is called for, if the callus is not yet firmly consolidated, it may be possible, under an anæsthetic, to bend the bone into position or to re-break it, either with the hands or by means of a strong mechanical contrivance known as an osteoclast.

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  • (C) Histomorphometric quantification of the trabecular bone volume and osteoclast surface per bone surface (OcS/BS).

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  • Tnfrsf11b, the gene encoding the osteoclast-inhibitory factor Opg, is known to be induced by canonical Wnt signaling in osteoblasts

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  • Col1a1-Krm2 mice display a cell-autonomous differentiation defect, impaired canonical Wnt signalling and decreased production of the osteoclast inhibitory factor Opg. To determine whether the observed effects of Krm2 on bone remodeling are physiologically relevant, we analyzed the skeletal phenotype of 24 weeks old

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  • Teitelbaum S, Ross FP (2003) Genetic regulation of osteoclast development and function.

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