5
diaphanous(adjective, light, weak, thin, feeble)
5
discarnate(adjective, body, abstract, theoretical, abstruse)
5
disembodied(adjective, body)
5
elusive(adjective, mysterious, evasive)
5
empty(adjective, slight, value, negative, insignificant)
5
gossamery(adjective, light, slight, easy, thin)
5
insecure(adjective, weak, delicate, false, unstable)
5
jejune
5
meager(adjective, mean, light, weak, slight)
5
meagre
5
petty(adjective, light, weak, slight, easy)
5
unbelievable(adjective, strange, fantasy, imaginary, unreal)
5
unstable(adjective, weak, delicate, false, short)
5
vaporous(adjective, negative, unstable, airy, absent)
5
weakly(adjective, strong, weak, thin, delicate)
4
aerial(adjective, light, weak, slight, fake)
4
artificial(adjective, fake, false, imaginary, fanciful)
4
delusive(adjective, fake, false, strange, fantasy)
4
fine(adjective, light, slight, delicate, flimsy)
4
fluffy(adjective, light, slight, easy, thin)
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APASmart Define. (2016). insubstantial thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/insubstantial/thesaurus/synonyms
ChicagoSmart Define. 2016. "insubstantial thesaurus" https://smartdefine.org/insubstantial/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, insubstantial thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/insubstantial/thesaurus/synonyms>.
MLASmart Define. "insubstantial thesaurus" 30 March 2016. Web. 25 September 2026. <https://smartdefine.org/insubstantial/thesaurus/synonyms>