/ Thesaurus / G Synonyms of geastrum Find synonyms for: Noun1. Geastrum, genus Geastrum, fungus genususage: type genus of Geastraceae; fungi whose outer peridium when dry splits into starlike segmentsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language