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cop·per 1 (kŏpər)
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n.
1. Symbol Cu A ductile, malleable, reddish-brown metallic element that is an excellent conductor of heat and electricity and is widely used for electrical wiring, water piping, and corrosion-resistant parts, either pure or in alloys such as brass and bronze. Atomic number 29; atomic weight 63.546; melting point 1,085°C; boiling point 2,562°C; specific gravity 8.96; valence 1, 2. See Periodic Table.
2. A coin, usually of small denomination, made of copper or a copper alloy.
3. Chiefly British A large cooking pot made of copper or often of iron.
4. Any of various small butterflies of the subfamily Lycaeninae, having predominantly copper-colored wings.
5. A reddish brown.
tr.v. cop·pered, cop·per·ing, cop·pers
1. To coat or finish with a layer of copper.
2. Slang To bet against, as in faro.

[Middle English coper, from Old English, from Late Latin cuprum, from Latin Cyprium (aes), Cyprian (metal), from Cyprius, of Cyprus, from Greek Kuprios, from Kupros, Cyprus.]

copper·y adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
cop·per 2 (kŏpər)
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n.
Slang
A police officer.

[From COP2.]

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.