/ Thesaurus / I Synonyms of insubstantially Find synonyms for: Adverb1. insubstantially, impalpablyusage: not substantially; lacking substantial expression or fullnessWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language