allactite

noun

al·​lac·​tite

əˈlakˌtīt

plural -s

: a mineral consisting of a brownish red basic manganese arsenate Mn₇(AsO₄)₂(OH)₈

Word History

Etymology

International Scientific Vocabulary allact- (irregular from Greek allag-, stem of allassein to change, from allos other) + -ite; originally formed as Swedish allaktit

First Known Use

1884, in the meaning defined above

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