/ Thesaurus / A Synonyms of atomic number 42 Find synonyms for: Noun1. molybdenum, Mo, atomic number 42, metallic element, metalusage: a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steelWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: acerbity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language