4
mind-blowing(adjective, unbelievable, unimaginable)
4
nice(great, excellent, superb, super, groovy)
4
offensive
4
outlandish(adjective, extraordinary, unusual, exceptional, absurd)
4
outstanding(great, excellent, superb, exceptional, special)
4
overwhelming(adjective, great, excellent, superb, super)
4
prohibited(offensive, permitted, prohibition, unmentionable)
4
questionable(adjective, extraordinary, amazing, unbelievable, implausible)
4
remarkable(great, excellent, superb, exceptional, special)
4
startling(great, excellent, unusual, superb, special)
4
terrific(great, excellent, superb, super, groovy)
4
unconvincing(adjective, extraordinary, strange, amazing, implausible)
4
unheard-of(adjective, extraordinary, strange, exceptional, marvelous)
4
unordinary(adjective, excellent, extraordinary, unusual, exceptional)
4
untold(adjective, many)
4
unworkable(adjective, possible, impossible)
3
adorable(great, excellent, superb, super, groovy)
3
aesthetic(great, excellent, superb, super, groovy)
3
agreeable(great, excellent, superb, super, groovy)
3
astounding(great, excellent, superb, super, groovy)
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APASmart Define. (2015). unthinkable thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/unthinkable/thesaurus/synonyms
ChicagoSmart Define. 2015. "unthinkable thesaurus" https://smartdefine.org/unthinkable/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2015, unthinkable thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/unthinkable/thesaurus/synonyms>.
MLASmart Define. "unthinkable thesaurus" 14 April 2015. Web. 25 September 2026. <https://smartdefine.org/unthinkable/thesaurus/synonyms>