1. [n]  any of various small butterflies of the family Lycaenidae having copper colored wings
2. [n]  a reddish brown the color of polished copper
3. [n]  (informal) uncomplimentary terms for a policeman
4. [n]  a copper penny
5. [n]  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
6. [v]  coat with a layer of copper

1. \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.
   
   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.
   
   2. A coin made of copper; a penny, cent, or other minor coin
      of copper. [Colloq.]
   
            My friends filled my pockets with coppers.
                                                  --Franklin.
   
   3. A vessel, especially a large boiler, made of copper.
   
   4. pl. Specifically (Naut.), the boilers in the galley for
      cooking; as, a ship's coppers.
   
   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.
   
               All in a hot and copper sky.       --Coleridge.
   
   Note: It is sometimes written in combination; as,
         copperplate, coppersmith, copper-colored.
   
   {Copper finch}. (Zo["o]l.) See {Chaffinch}.
   
   {Copper glance}, or {Vitreous copper}. (Min.) See
      {Chalcocite}.
   
   {Indigo copper}. (Min.) See {Covelline}.
   
   

2. \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.
   
   

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]

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).