Synonyms for Uncommon (same or very similar meaning)
WordNet sense 1 (beyond what is ordinary or usual; highly unusual or exceptional or remarkable):
extraordinary
WordNet sense 2 (out of the ordinary):
unwonted
WordNet sense 3 (not commonly encountered):
unusual
WordNet sense 4 (not widely known; especially valued for its uncommonness):
rare
WordNet sense 5 (surpassing what is common or usual or expected):
exceptional, special
From the ODE community, based on WordNet
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