[kyoo-pruh-nik-uh
l, koo-] 
| 1. | any of various alloys of copper containing up to 40 percent nickel. |
| 2. | containing copper and nickel. |
| cu·pro·nick·el (kōō'prō-nĭk'əl, kyōō'-) n. An alloy of copper that contains 10 to 30 percent nickel. |
cupronickel
any of an important group of alloys of copper and nickel; the alloy containing 25 percent nickel is used by many countries for coins. Because copper and nickel mix readily in the molten state, the useful range of alloys is not confined within any definite limits. Additions of from 2 percent to 45 percent of nickel to copper provide a series of alloys that are stronger and more resistant to oxidation at high temperatures than is pure copper. An alloy containing 30 percent nickel, the most important, is widely used for condenser tubes in steam-power plants.
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