/ Thesaurus / A Synonyms of atomic number 77 Find synonyms for: Noun1. iridium, Ir, atomic number 77, metallic element, metalusage: a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmiumWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: lyre Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language