First class and Unknown

Opposite meaning terms

First class noun - Mail that includes letters and postcards and packages sealed against inspection.

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Unknown is an antonym for first class in topics: superior, excellent, eminent.

Unknown adjective - Happening or existing without one's knowledge.

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First class is an antonym for unknown.

Nearby Words: unknowable, unknowing

Cite this Source

Unknown and First class. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/first_class/unknown

First class & Unknown. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/first_class/unknown>.

Unknown or First class. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/first_class/unknown.

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