Synonyms|630Antonyms|141|Broader|15Narrower|8Related|1k
15
impossible
8
implausible(adjective, reasonable, plausible)
8
unlikely(adjective, reasonable, unreasonable, likely)
6
improbable(adjective, unreasonable, likely, unlikely)
5
inconceivable(adjective, reasonable, unreasonable, unlikely, imaginable)
4
incredible(adjective, bad, unremarkable)
2
impracticable
2
unattainable
2
dubious
2
unbelievable(adjective, plausible)
2
impractical(adjective, practical)
1
hopeless
1
unachievable
1
definite
1
factual
1
fantastic
1
far-fetched
1
genuine
1
infeasible
1
real
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APASmart Define. (2015). possible thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/possible/thesaurus/antonyms
ChicagoSmart Define. 2015. "possible thesaurus" https://smartdefine.org/possible/thesaurus/antonyms (accessed September 23, 2026).
HarvardSmart Define 2015, possible thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/possible/thesaurus/antonyms>.
MLASmart Define. "possible thesaurus" 10 April 2015. Web. 23 September 2026. <https://smartdefine.org/possible/thesaurus/antonyms>