5
vague(adjective, excellent, gentle, obscure, negative)
5
weakly(adjective, strong, weak, delicate, uncertain)
5
weightless(adjective, light, slight, easy, thin)
4
apparitional(adjective, fantastic, heavenly, unreal, theoretical)
4
artificial(adjective, imaginary, illusory, dreamlike)
4
baseless(unsubstantiality, inexistence)
4
chimeric(adjective, strange, fantasy, unreal)
4
cranky(adjective, weakness, strange, fantasy, unreal)
4
dainty(adjective, light, weak, slight, easy)
4
dreamlike(adjective, negative, fantastic, heavenly, unreal)
4
dreamy(adjective, gentle, obscure, marvelous, heavenly)
4
empty(adjective, ineffective, fruitless)
4
erroneous(bad, false, ill, error, insane)
4
faint(adjective, dull, light, weak, soft)
4
ghostly(adjective, obscure, vague, heavenly, incorporeal)
4
gimcrack(adjective, weakness)
4
gossamery(adjective, light, slight, easy, thin)
4
illogical(adjective, false, sense, unstable, ill)
4
inconsequential(adjective, light, weak, soft, slight)
4
less(adjective, inferior, smaller)
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APASmart Define. (2016). unsubstantial thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/unsubstantial/thesaurus/synonyms
ChicagoSmart Define. 2016. "unsubstantial thesaurus" https://smartdefine.org/unsubstantial/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, unsubstantial thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/unsubstantial/thesaurus/synonyms>.
MLASmart Define. "unsubstantial thesaurus" 30 March 2016. Web. 25 September 2026. <https://smartdefine.org/unsubstantial/thesaurus/synonyms>