noun jef·fer·son·ite \ˈjefə(r)səˌnīt\

Definition of jeffersonite



  1. :  a mineral Ca(Mn,Zn,Fe)Si2O6 consisting of a dark green or greenish black pyroxene

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Origin and Etymology of jeffersonite

Thomas Jefferson + English -ite

Seen and Heard

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a rounded knoll or a ridge of ice

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