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

Word History


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

Time Traveler
The first known use of allactite was in 1884

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Dictionary Entries Near allactite

Cite this Entry

“Allactite.” Dictionary, Merriam-Webster, Accessed 31 Mar. 2023.

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