11
unsound(adjective, bad, strong, light, weak)
10
decrepit(adjective, strong, light, weak, slight)
10
delicate(adjective, strong, light, weak, slight)
10
illusory(adjective, light, weak, slight, strange)
10
incorporeal(adjective, body, light, abstract, heavenly)
10
infirm(adjective, strong, light, weak, slight)
10
rickety(adjective, weak, slight, weakness, thin)
10
shadowy(adjective, gentle, obscure, substance, marvelous)
9
airy(adjective, light, weak, slight, easy)
9
bodiless(adjective, body, abstract, heavenly, theoretical)
9
impalpable(adjective, abstract, heavenly, theoretical, immaterial)
9
insignificant(adjective, weak, soft, gentle, mild)
9
tenuous(adjective, strong, light, weak, slight)
8
diaphanous(adjective, weak, slight, thin, substance)
8
puny(adjective, strong, light, weak, soft)
7
chimerical(adjective, light, weak, slight, gentle)
7
delusive(adjective, strange, trivial, fantasy, insufficient)
7
disembodied(adjective, body, heavenly, incorporeal, nonmaterial)
7
fanciful(adjective, light, gentle, strange, fantasy)
7
implausible(adjective, thin, extraordinary, strange, unreasonable)
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APASmart Define. (2016). unsubstantial thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/unsubstantial/thesaurus/synonyms
ChicagoSmart Define. 2016. "unsubstantial thesaurus" https://smartdefine.org/unsubstantial/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, unsubstantial thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/unsubstantial/thesaurus/synonyms>.
MLASmart Define. "unsubstantial thesaurus" 30 March 2016. Web. 24 September 2026. <https://smartdefine.org/unsubstantial/thesaurus/synonyms>