/ Thesaurus / I Synonyms of i beam Find synonyms for: Noun1. I-beam, girderusage: girder having a cross section resembling the letter `I'WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: penury Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language