/ Dictionary / Index C clausthalite: Meaning and Definition of Find definitions for: claus•thal•ite Pronunciation: (klou'stu-līt"), [key] — n. a rare mineral, lead selenide, PbSe, occurring in grayish, granular crystals that have a metallic luster. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Clausius cycle claustral Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language