Synonyms for Copper (same or very similar meaning)
WordNet sense 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):
Cu
WordNet sense 2 (uncomplimentary terms for a policeman):
bull, cop, fuzz, pig
WordNet sense 3 (a reddish-brown color resembling the color of polished copper):
copper color
From the ODE community, based on WordNet
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