chalco-

chalco-

or before a vowel

chalc-

combining form
(Chemistry) indicating copper or a copper alloy: chalcopyrite; chalcolithic.
[from Greek khalkos copper]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

chalco-

a combining form meaning “copper”: chalcopyrite.
[< Greek chalko-, comb. form of chalkós copper]
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