12
ethereal(adjective, light, slight, easy, thin)
12
imaginary(adjective, strange, negative, fantasy, imaginary)
11
decrepit(adjective, strong, light, weak, slight)
11
delicate(adjective, strong, light, weak, slight)
10
ephemeral(adjective, light, weak, slight, short)
10
gossamer(adjective, light, thin, feeble, flimsy)
10
light(adjective, weak, soft, slight, thin)
10
unsound(adjective, strong, light, weak, slight)
10
visionary(adjective, fake, false, strange, fantasy)
9
paltry(adjective, weak, slight, thin, delicate)
9
puny(adjective, strong, light, weak, slight)
9
trifling(adjective, light, slight, easy, thin)
8
impalpable(adjective, fake, false, abstract, fanciful)
8
inconsequential(adjective, light, slight, easy, thin)
8
infirm(adjective, strong, light, weak, slight)
8
rickety(adjective, weak, slight, weakness, thin)
8
shadowy(adjective, unsubstantiality, inexistence)
7
bodiless(adjective, body, abstract, theoretical, abstruse)
7
false(adjective, light, weak, slight, fake)
7
fancied(adjective, strange, negative, fantasy, unreal)
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APASmart Define. (2016). insubstantial thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/insubstantial/thesaurus/synonyms
ChicagoSmart Define. 2016. "insubstantial thesaurus" https://smartdefine.org/insubstantial/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, insubstantial thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/insubstantial/thesaurus/synonyms>.
MLASmart Define. "insubstantial thesaurus" 30 March 2016. Web. 24 September 2026. <https://smartdefine.org/insubstantial/thesaurus/synonyms>