What is pertaining to, or containing, nickel; specifically, designating compounds in which, as contrasted with the nickelous compounds, the metal has a higher valence; as nickelic oxide called?

nickelic — Pertaining to, or containing, nickel; specifically, designating compounds in which, as contrasted with the nickelous compounds, the metal has a higher valence; as nickelic oxide. (Webster's 1913.)

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