Synonyms|251Antonyms|96|Broader|0Narrower|0Related|837
10
unsustainable
7
impossible
7
unworkable
2
futile
2
unfeasible
1
impracticable
1
impractical
1
dead
1
hopeless
1
inconceivable
1
incredible
1
infeasible
1
ridiculous
1
unachievable
1
unattainable
1
unlikely
1
unrealistic
1
unreasonable
1
useless
0
improbable
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APASmart Define. (2016). viable thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/viable/thesaurus/antonyms
ChicagoSmart Define. 2016. "viable thesaurus" https://smartdefine.org/viable/thesaurus/antonyms (accessed September 20, 2026).
HarvardSmart Define 2016, viable thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/viable/thesaurus/antonyms>.
MLASmart Define. "viable thesaurus" 29 March 2016. Web. 20 September 2026. <https://smartdefine.org/viable/thesaurus/antonyms>