/ Thesaurus / D Synonyms of dewar flask Find synonyms for: Noun1. Dewar flask, Dewar, vacuum flask, vacuum bottleusage: vacuum flask that holds liquid air or helium for scientific experimentsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: heifer Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language