Meaning of sillimanite

sil•li•man•ite

Pronunciation: (sil'u-mu-nīt"), [key]
— n.
  1. a mineral, aluminum silicate, AlSiO, occurring in the form of long, slender, and often fibrous crystals. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.