2
apocryphal
2
asomatous(heavenly, incorporeal, nonmaterial)
2
astral(excellent, gentle, marvelous, vague, dreamy)
2
attenuate(adjective, fine, thin, delicate, slim)
2
attenuated(adjective, fine, thin, delicate, slim)
2
cobwebby
2
conceptual(adjective, immaterial)
2
crumbling
2
crumbly(adjective, light, slight, easy, thin)
2
dangerous(false, unstable, ill, shaky, insane)
2
debilitated(adjective, weak, delicate, uncertain, ill)
2
dilapidated
2
dim(adjective, dull, light, soft, obscure)
2
doubtful(extraordinary, unreasonable, amazing, dubious, unlikely)
2
dubious(extraordinary, unreasonable, amazing, doubtful, unlikely)
2
effete(adjective, uncertain, feeble, shaky, hesitant)
2
enervated(adjective, uncertain, feeble, shaky, hesitant)
2
enfeebled(adjective, weak, delicate, ill, sick)
2
fleeting
2
futile(adjective, hopeless, pointless)
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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>