plural -s
: a mineral H2Na6(Mn,Fe,Ca)14(PO4)12.H2O(?) consisting of a brown, yellow, or colorless hydrous phosphate of manganese, iron, sodium, and other metals

Word History


A. N. Fillow, 19th century American mine owner + English -ite

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Dictionary Entries Near fillowite

Cite this Entry

“Fillowite.” Dictionary, Merriam-Webster, Accessed 25 Jun. 2024.

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