/ Thesaurus / G Synonyms of genus hyracotherium Find synonyms for: Noun1. Hyracotherium, genus Hyracotherium, mammal genususage: extinct horse genus; formerly called eohippusWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language