sil·​li·​man·​ite ˈsi-lə-mə-ˌnīt How to pronounce sillimanite (audio)
: a brown, grayish, or pale green mineral that consists of an aluminum silicate in orthorhombic crystals often occurring in fibrous or columnar forms

Word History


Benjamin Silliman †1864 American geologist

First Known Use

circa 1830, in the meaning defined above

Time Traveler
The first known use of sillimanite was circa 1830

Dictionary Entries Near sillimanite

Cite this Entry

“Sillimanite.” Dictionary, Merriam-Webster, Accessed 30 Mar. 2023.

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