/ Thesaurus / G Synonyms of genus rhizobium Find synonyms for: Noun1. Rhizobium, genus Rhizobium, bacteria genususage: the type genus of Rhizobiaceae; usually occur in the root nodules of legumes; can fix atmospheric oxygenWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: mongrel Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language