noun sel·e·no·ni·um \ˌseləˈnōnēəm\

Definition of selenonium



  1. :  a univalent cation SeH3+ or radical SeH3 analogous to sulfonium with selenium in place of sulfur

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Origin and Etymology of selenonium

New Latin, from 2selen- + -onium

Seen and Heard

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feeling or affected by lethargy

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