Breadcrumb Home > Thesaurus > U Synonyms of unsubstantial Find synonyms for: Adjective 1. insubstantial (vs. substantial), unsubstantial, unreal, aeriform, aerial, airy, aery, ethereal, shadowy, wraithlike, stringy, immaterial#3, nonmaterial usage: lacking material form or substance; unreal; "as insubstantial as a dream"; "an insubstantial mirage on the horizon" WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of unsubstantial (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Chinese New Year History, Meaning, and Celebrations Current Events This Week: February 2024 Valentine's Day Valentine's Day History Mardi Gras 30 "Charlie and the Chocolate Factory" Quotes ✖ Related Content Daily Word Quiz: stygian Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language