The Collaborative International Dictionary of English v.0.48:

Copper \Cop"per\, n. [OE. coper (cf. D. koper, Sw. koppar, Dan.
   kobber, G. kupfer), LL. cuper, fr. L. cuprum for earlier
   Cyprium, Cyprium aes, i.e., Cyprian brass, fr. Gr. ? of
   Cyprus (Gr. ?), anciently renowned for its copper mines. Cf.
   Cypreous.]
   1. A common metal of a reddish color, both ductile and
      malleable, and very tenacious. It is one of the best
      conductors of heat and electricity. Symbol Cu. Atomic
      weight 63.3. It is one of the most useful metals in
      itself, and also in its alloys, brass and bronze.
      [1913 Webster]

   Note: Copper is the only metal which occurs native abundantly
         in large masses; it is found also in various ores, of
         which the most important are chalcopyrite, chalcocite,
         cuprite, and malachite. Copper mixed with tin forms
         bell metal; with a smaller proportion, bronze; and with
         zinc, it forms brass, pinchbeck, and other alloys.
         [1913 Webster]

   2. A coin made of copper; a penny, cent, or other minor coin
      of copper. [Colloq.]
      [1913 Webster]

            My friends filled my pockets with coppers.
                                                  --Franklin.
      [1913 Webster]

   3. A vessel, especially a large boiler, made of copper.
      [1913 Webster]

   4. pl. Specifically (Naut.), the boilers in the galley for
      cooking; as, a ship's coppers.
      [1913 Webster]

   Note: Copper is often used adjectively, commonly in the sense
         of made or consisting of copper, or resembling copper;
         as, a copper boiler, tube, etc.
         [1913 Webster]

               All in a hot and copper sky.       --Coleridge.
         [1913 Webster]

   Note: It is sometimes written in combination; as,
         copperplate, coppersmith, copper-colored.
         [1913 Webster]

   Copper finch. (Zool.) See Chaffinch.

   Copper glance, or Vitreous copper. (Min.) See
      Chalcocite.

   Indigo copper. (Min.) See Covelline.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Copper \Cop"per\, v. t. [imp. & p. p. Coppered; p. pr. & vb.
   n. Coppering.]
   To cover or coat with copper; to sheathe with sheets of
   copper; as, to copper a ship.
   [1913 Webster]

WordNet (r) 3.0 (2006):

copper
    n 1: a ductile malleable reddish-brown corrosion-resistant
         diamagnetic metallic element; occurs in various minerals
         but is the only metal that occurs abundantly in large
         masses; used as an electrical and thermal conductor [syn:
         copper, Cu, atomic number 29]
    2: a copper penny
    3: uncomplimentary terms for a policeman [syn: bull, cop,
       copper, fuzz, pig]
    4: a reddish-brown color resembling the color of polished copper
       [syn: copper, copper color]
    5: any of various small butterflies of the family Lycaenidae
       having coppery wings
    v 1: coat with a layer of copper

Moby Thesaurus II by Grady Ward, 1.0:

143 Moby Thesaurus words for "copper":
   C, C-note, Dogberry, G, G-note, John Law, Titian, adust, auburn,
   aureate, bar, bay, bay-colored, bayard, bluecoat, bobby, brass,
   brassy, brazen, bronze, bronze-colored, bronzed, bronzy,
   brownish-red, buck, bull, bullion, cartwheel, castaneous, cent,
   century, chestnut, chestnut-brown, coin gold, coin silver, cop,
   copper-colored, coppery, cupreous, cuprous, dick, dime, dollar,
   dollar bill, ferrous, ferruginous, fifty cents, fin, fish,
   five cents, five hundred dollars, five-dollar bill,
   five-hundred-dollar bill, five-spot, fiver, flatfoot, flattie,
   four bits, foxy, frogskin, fuzz, gendarme, gilt, gold, gold nugget,
   gold-filled, gold-plated, golden, grand, gumshoe, half G, half a C,
   half dollar, half grand, heat, henna, hundred-dollar bill, ingot,
   iron, iron man, ironlike, lead, leaden, liver-brown, liver-colored,
   livid-brown, mahogany, man, mercurial, mercurous, mill, nickel,
   nickelic, nickeline, nugget, officer, peeler, penny, pewter,
   pewtery, pig, precious metals, quarter, quicksilver, red cent,
   reddish-brown, roan, rubiginous, rufous, russet, russety, rust,
   rust-colored, rusty, sawbuck, shamus, silver, silver dollar,
   silver-plated, silvery, skin, smacker, steel, steely, sunburned,
   ten cents, ten-spot, tenner, terra-cotta, the cops, the fuzz,
   the law, thousand dollars, thousand-dollar bill, tin, tinny,
   twenty-dollar bill, twenty-five cents, two bits, two-dollar bill,
   two-spot, yard, yellow stuff



The Elements (07Nov00):

copper
Symbol: Cu
Atomic number: 29
Atomic weight: 63.54
Red-brown transition element. Known by the Romans as 'cuprum.' Extracted
and used for thousands of years. Malleable, ductile and an excellent
conductor of heat and electricity. When in moist conditions, a greenish
layer forms on the outside.


The Jargon File (version 4.4.7, 29 Dec 2003):

copper
 n.

    Conventional electron-carrying network cable with a core conductor of
    copper ? or aluminum! Opposed to light pipe or, say, a short-range
    microwave link.


The Free On-line Dictionary of Computing (30 December 2018):

copper

   Conventional electrical network cable with a core conductor of
   copper (or aluminium!)

   Opposed to light pipe or, say, a short-range microwave link.

   [Jargon File]

   (1994-11-30)


Easton's 1897 Bible Dictionary:

Copper
   derived from the Greek kupros (the island of Cyprus), called
   "Cyprian brass," occurs only in the Authorized Version in Ezra
   8:27. Elsewhere the Hebrew word (nehosheth) is improperly
   rendered "brass," and sometimes "steel" (2 Sam. 22:35; Jer.
   15:12). The "bow of steel" (Job 20:24; Ps. 18:34) should have
   been "bow of copper" (or "brass," as in the R.V.). The vessels
   of "fine copper" of Ezra 8:27 were probably similar to those of
   "bright brass" mentioned in 1 Kings 7:45; Dan. 10:6.

     Tubal-cain was the first artificer in brass and iron (Gen.
   4:22). Hiram was noted as a worker in brass (1 Kings 7:14).
   Copper abounded in Palestine (Deut. 8:9; Isa. 60:17; 1 Chr.
   22:3, 14). All sorts of vessels in the tabernacle and the temple
   were made of it (Lev. 6:28; Num. 16:39; 2 Chr. 4:16; Ezra 8:27);
   also weapons of war (1 Sam. 17:5, 6, 38; 2 Sam. 21:16). Iron is
   mentioned only four times (Gen. 4:22; Lev. 26:19; Num. 31:22;
   35:16) in the first four books of Moses, while copper (rendered
   "brass") is mentioned forty times. (See BRASS.)

     We find mention of Alexander (q.v.), a "coppersmith" of
   Ephesus (2 Tim. 4:14).