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REFERENCE

copper

n. · adj. · v.
US //ˈkɑpɝ// UK //kˈɒpɐ// cop·per
  1. 1 the metal (n.)
    B1 Intermediate Science

    a soft, reddish-brown metal that allows electricity and heat to pass through it easily.

    a ductile, malleable metallic element (symbol Cu) with high thermal and electrical conductivity.

    Example

    Most electrical wires in your home are made of copper because it is a great conductor.

    Example

    The price of copper fluctuated wildly on the global market as industrial demand for new infrastructure increased throughout the decade.

  2. 2 police officer (n.)
    B2 Upper Intermediate British English Informal Slang

    a slang word for a police officer.

    a colloquial term for a police officer, primarily used in British and Australian English.

    Example

    The thief ran down the alley when he saw a copper coming around the corner.

    Example

    He spent half his life dodging coppers in the East End before finally deciding to go straight and open a legitimate business.

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  1. 3 the color (n.)
    B2 Upper Intermediate

    a reddish-brown color like the metal copper.

    a reddish-brown hue resembling the appearance of polished or weathered copper metal.

    Example

    The autumn leaves turned a beautiful shade of copper before falling to the ground.

    Example

    The interior designer recommended accents of copper and deep teal to create a warm, sophisticated atmosphere in the study.

    • reddish brown
    • russet
  2. 4 made of or colored like copper (adj.)
    B1 Intermediate

    made of copper or having a reddish-brown color.

    composed of the element copper or possessing its characteristic reddish-brown color.

    Example

    She wore a copper bracelet that she bought at the local craft market.

    Example

    The building was topped with a copper roof that had developed a distinctive green patina over decades of exposure to the elements.

  3. 5 to cover with copper (v.)
    C2 Proficiency Technical Formal Technical

    to cover something with a thin layer of copper.

    to coat, plate, or sheathe an object with a layer of copper.

    Example

    The artist decided to copper the bottom of the sculpture to protect it from water.

    Example

    The hull was coppered to prevent the growth of marine organisms and to protect the timber from wood-boring worms during long voyages.

Etymology 1

The noun is inherited from Middle English coper, copper (“copper ore; copper metal; bronze”), from Old English coper, copor (“copper”), from Late Latin cuprum (“copper”), a contraction of Latin aes Cyprium (literally “Cyprian brass or copper”), ultimately from Ancient Greek Κῠ́προς (Kŭ́pros, “Cyprus”) (a major source of copper during the Near East’s Bronze Age), from the name of a Northwest Semitic goddess from the root כ־ב־ר/ك ب ر (k b r) (“related to being big, large; great; or old”). Doublet of kobo. The adjective is from an attributive use of the noun. The verb is also derived from the noun. cognates * Dutch koper (“copper”) * German Kupfer (“copper”) * Icelandic kopar (“copper”)

Etymology 2

The noun is probably derived from cop (“(informal, dated) to arrest or capture (someone)”) + -er (suffix forming agent nouns), although cop is attested slightly later. The verb is derived from the noun.

Etymology 3

From cop (“ball of thread wound on to a spindle in a spinning machine”) + -er (suffix denoting things relating to the words to which the suffix is attached to).

Idioms1 entry

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