Etymologically

copper

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English has two words spelled copper: the metal, and the slang word for a police officer.[1][2][3]

Pronunciation

  • IPA: /ˈkɒpə/, /ˈkɑpəɹ/[4]

copper1 metal

Etymology

The metal is Middle English coper, inherited from Old English coper (“copper”),[1][2][5] an early Germanic borrowing, like Middle Dutch coper, Old Norse koparr and Old High German kupfar,[1][3] of Late Latin cuprum, from Latin Cyprium in aes Cyprium (“metal of Cyprus”),[1][5][2] from Ancient Greek Κύπρος (Kúpros, “Cyprus”), the island that was its chief ancient source.[1][2]

Earliest recorded meaning

The red metal: about 1000 in Barnhart and the OED, late Old English in Etymonline.[1][6][5]

Semantic evolution

Copper money, and a copper coin such as a penny, is from 1588.[6][2] A large copper vessel, especially a boiler for laundry, is from 1667.[6] The colour, reddish brown, is also called copper.[7][8] The verb, to cover with copper, is from the mid-16th century, 1530 in MWU, and in faro to bet against a card by placing a copper coin on it, from the 19th century.[9][3]

Timeline

  • c. 1000 – the metal.[1][6]
  • 1588 – a copper coin.[6]
  • 1667 – a copper boiler.[6]

Modern meaning

Noun

  1. A reddish-brown metallic element, symbol Cu, a good conductor of heat and electricity, used in wiring and in alloys such as brass and bronze.
  2. A coin of copper or bronze, such as a penny.
  3. A large copper or iron vessel for boiling, especially laundry.
  4. A reddish-brown colour.

Verb

  1. To coat or cover with copper.

Word family

  • coppery
  • copperplate
  • coppersmith
  • copperhead

copper2 police officer

Etymology

The police officer is formed from the slang verb cop, to catch or arrest, and -er.[1][5][3][9] Word Origins derives cop from a northern dialect word cap, to arrest, probably from Latin capere (“to take, seize”), so that a copper was a catcher.[10]

Earliest recorded meaning

A policeman: 1846.[1][5][3]

Semantic evolution

The shortened cop followed.[10] In slang to turn copper is to inform on others, and the verb copper is to arrest or to inform the police (late 19th century).[9]

Timeline

Modern meaning

Noun

  1. (informal) A police officer.
  • copperas
  • cupr-
  • cupreous
  • cupric
  • cupriferous
  • cuprite
  • cupro-
  • cuprous
  • cop
  • Cyprus

References

  1. ^ a b c d e f g h i j Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  2. ^ a b c d e Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  3. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  4. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
  5. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  6. ^ a b c d e f Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
  7. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
  8. ^ Collins English Dictionary (2023), Glasgow: HarperCollins
  9. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
  10. ^ a b Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press