6
doubtful(adjective, extraordinary, amazing, dubious, unlikely)
6
fanciful(great, excellent, superb, super, doubtful)
6
phenomenal(great, excellent, superb, super, groovy)
6
remarkable(great, excellent, superb, exceptional, special)
6
staggering(adjective, great, excellent, extraordinary, superb)
6
strange(adjective, light, extraordinary, exceptional, marvelous)
6
uncommon(adjective, light, thin, wonderful, exceptional)
6
unexpected(great, excellent, superb, super, groovy)
6
unheard-of(adjective, extraordinary, strange, exceptional, special)
6
unlikely(adjective, light, extraordinary, strange, rare)
5
absurd(adjective, unreasonable, useless, doubtful, dubious)
5
astonishing(adjective, great, excellent, strange, superb)
5
astounding(adjective, great, excellent, superb, super)
5
beyond belief(expression, adjective, idiom, extraordinary, belief)
5
exceptional(adjective, light, thin, marvelous, special)
5
farfetched
5
fascinating(great, excellent, superb, super, groovy)
5
good(great, excellent, superb, super, groovy)
5
prodigious(extraordinary, strange, exceptional, marvelous, wonder)
5
singular(adjective, light, thin, strange, exceptional)
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APASmart Define. (2015). unimaginable thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/unimaginable/thesaurus/synonyms
ChicagoSmart Define. 2015. "unimaginable thesaurus" https://smartdefine.org/unimaginable/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2015, unimaginable thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/unimaginable/thesaurus/synonyms>.
MLASmart Define. "unimaginable thesaurus" 14 April 2015. Web. 26 September 2026. <https://smartdefine.org/unimaginable/thesaurus/synonyms>