copper

1 of 3

noun (1)

cop·​per ˈkä-pər 

plural coppers

1

: a metallic chemical element with atomic number 29 that is easily formed into sheets and wires and is one of the best known conductors of heat and electricity

—often used before another noun

copper wire

a copper mug

copper mines

see Chemical Elements Table

2

: a coin or token made of copper or bronze

3

chiefly British : a large boiler (as for cooking)

4

: any of a subfamily (Lycaeninae of the family Lycaenidae) of small butterflies with usually copper-colored wings

copper

2 of 3

verb

coppered; coppering ˈkä-p(ə-)riŋ 

transitive verb

: to coat or sheathe with or as if with copper

copper

3 of 3

noun (2)

plural coppers

: police officer

Synonyms of copper

Noun (2)

• policeman
• officer
• cop
• constable

Examples of copper in a Sentence

Noun (2)

a crime novel set in the days when policemen were coppers and safecrackers were "yeggs"

Recent Examples on the Web

Noun

Researchers placed the masses on flat platelike objects called torsion disks, with the lighter masses on the inside suspended by a thin copper beryllium strip and the heavier masses located on a separate disk on the outside. —Emma Gometz, Scientific American, 24 Apr. 2026

The increasing use of fiber-optic cables instead of copper wiring inside data centers is a big win for Corning, Cramer said. —Alexa Lomonaco, CNBC, 24 Apr. 2026

The bronze and copper mirrors were crafted by French sculptor and designer Claude Lalanne, and this new high auction going price sets a new record for the artist. —News Desk, Artforum, 23 Apr. 2026

Today’s issue of Science includes a paper describing the addition of a chemical to carbon nanotube bundles to boost their ability to carry current to levels closer to those of copper. —ArsTechnica, 23 Apr. 2026

Word History

Etymology

Noun (1)

Middle English coper, from Old English, from Late Latin cuprum copper, from Latin (aes) Cyprium, literally, Cyprian metal

Noun (2)

cop entry 2

First Known Use

Noun (1)

before the 12th century, in the meaning defined at sense 1

Verb

1530, in the meaning defined above

Noun (2)

1846, in the meaning defined above

Phrases Containing copper

• chromated copper arsenate
• copper beech
• copper-bottomed
• copper pyrites
• copper sulfate

Rhymes for copper

• chopper
• cropper
• dropper
• pauper
• popper
• proper
• shopper
• stopper
• topper
• whopper
• eavesdropper
• grasshopper

Kids Definition

copper

1 of 2 noun

cop·​per ˈkäp-ər 

1

: a reddish metallic element that is one of the best conductors of heat and electricity see element

2

: a copper or bronze coin

3

chiefly British : a large copper kettle or boiler

4

: any of various small butterflies with usually copper-colored wings

coppery

ˈkäp-(ə-)rē

adjective

copper

2 of 2 noun

: police officer

Medical Definition

copper

noun

cop·​per ˈkäp-ər 

: a metallic chemical element with atomic number 29 that is ductile and malleable and one of the best conductors of heat and electricity

—symbol Cu see Chemical Elements Table

coppery

ˈkäp-(ə-)rē 

adjective