/ Dictionary / Index H hyolithid: Meaning and Definition of Find definitions for: hy•ol•i•thid Pronunciation: (hī-ol'i-thid), [key] — n. any invertebrate of the extinct genus Hyolithes, most common in the Cambrian Period, having a limy, univalve shell, and thought to be related to the pteropods. —adj. belonging or pertaining to Hyolithes. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hyoid hyoscine Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language