noun sil·li·man·ite \ˈsi-lə-mə-ˌnīt\

Definition of sillimanite

  1. :  a brown, grayish, or pale green mineral that consists of an aluminum silicate in orthorhombic crystals often occurring in fibrous or columnar forms

Origin and Etymology of sillimanite

Benjamin Silliman †1864 American geologist

First Known Use: circa 1830

Learn More about sillimanite

Seen and Heard

What made you want to look up sillimanite? Please tell us where you read or heard it (including the quote, if possible).