Definition of spinel
1 : a hard crystalline mineral consisting of an oxide of magnesium and aluminum that varies from colorless to ruby red to black and is used as a gem
2 : any of a group of minerals that are essentially oxides of magnesium, ferrous iron, zinc, or manganese
Origin and Etymology of spinel
Italian spinella, diminutive of spina thorn, from Latin
First Known Use: 1528
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