/ Dictionary / Index H hyracotherium: Meaning and Definition of Find definitions for: hy•ra•co•the•ri•um Pronunciation: (hī"ru-kō-thēr'ē-um), [key] — pl. -the•ri•a eohippus. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: hyracotherium (Thesaurus) hypsometry hyrax Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language