10
unannounced
10
unplanned(adjective, chance, impulsive, planned, unqualified)
9
casual(adjective, careless, chance, random, arbitrary)
9
hasty(adjective, passionate, violent, fast, quick)
9
rare(adjective, extraordinary, unusual, strange, exceptional)
9
unlooked-for(adjective, surprising, unforeseen, unanticipated, unpredicted)
8
swift(adjective, passionate, violent, fast, quick)
8
abnormal(adjective, unusual, exceptional, special, irregular)
8
amazing(adjective, great, excellent, unusual, strange)
8
bizarre(adjective, obscure, unusual, strange, new)
8
eye-opening(adjective, amazing, shocking, astonishing, astounding)
8
fabulous(great, excellent, superb, super, groovy)
8
marvelous(great, excellent, unusual, strange, superb)
8
quick(adjective, passionate, violent, fast, abrupt)
8
uncommon(adjective, obscure, extraordinary, unusual, strange)
8
unfamiliar(adjective, unusual, strange, new, exceptional)
8
unheralded(adjective, surprising, unforeseen, unanticipated, unpredicted)
8
unpredictable(adjective, passionate, violent, uncertain, thoughtless)
7
charming(great, excellent, superb, super, groovy)
7
lovely(great, excellent, superb, super, groovy)
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APASmart Define. (2015). unexpected thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/unexpected/thesaurus/synonyms
ChicagoSmart Define. 2015. "unexpected thesaurus" https://smartdefine.org/unexpected/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, unexpected thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/unexpected/thesaurus/synonyms>.
MLASmart Define. "unexpected thesaurus" 13 April 2015. Web. 22 September 2026. <https://smartdefine.org/unexpected/thesaurus/synonyms>