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ce·men·tum (sĭ-mĕntəm) also ce·ment (-mĕnt)
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n.
A bonelike substance covering the root of a tooth.

[New Latin, from Latin caementum, rough stone; see CEMENT.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
ce·ment (sĭ-mĕnt)
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n.
1.
a. A building material made by grinding calcined limestone and clay to a fine powder, which can be mixed with water and poured to set as a solid mass or used as an ingredient in making mortar or concrete.
b. Portland cement.
c. Concrete.
2. A substance that hardens to act as an adhesive; glue.
3. Something that serves to bind or unite: “Custom was in early days the cement of society” (Walter Bagehot).
4. Geology A chemically precipitated substance that binds particles of clastic rocks.
5. Dentistry A substance used for filling cavities or anchoring crowns, inlays, or other restorations.
6. Variant of cementum.
v. ce·ment·ed, ce·ment·ing, ce·ments
v. tr.
1. To join or cover with cement: The workers cemented bricks in the wall.
2. To make binding; establish or strengthen: Signing the contract cemented the partners' agreement.
v. intr.
To become cemented.
Idiom:
in cement
Firmly settled or determined; unalterable: The administration's position on taxes was set in cement despite the unfavorable public response.

[Middle English, from Old French ciment, from Latin caementum, rough-cut stone, rubble used in making concrete, from caedere, to cut; see kaə-id- in the Appendix of Indo-European roots.]

ce·menter n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.