Synonyms|860Antonyms|162|Broader|10Narrower|5Related|1.4k
2
flitting
2
flying
2
frangible(adjective, weak, delicate, infirm, flimsy)
2
frothy(adjective, light, slight, easy, thin)
2
fugacious
2
fugitive
2
gaseous(adjective, ghostly, unearthly, otherworldly, wraithlike)
2
ghostly
2
gingerbread
2
hallucinational(adjective, strange, fantasy, unreal)
2
hallucinative(adjective, strange, fantasy, unreal)
2
hazardous(unstable, vulnerable, dangerous, unprotected, precarious)
2
hollow(adjective, slight, value, insignificant, unimportant)
2
hypothetical(negative, abstract, theoretical, imperceptible, vacant)
2
impermanent
2
incongruous(adjective, false, strange, fantasy, insane)
2
incredible(adjective, strange, fantasy, imaginary, unreal)
2
indefinite(adjective, imperceptible, immaterial, incorporeal)
2
insincere(fake, false, empty, worthless, imaginary)
2
insufficient(adjective, weak, slight, flat, poor)
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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>