Not known
Unknown
Unknown adjective - Happening or existing without one's knowledge.
Not known and unknown are semantically related. You can use "Not known" instead an adjective "Unknown".
Nearby Words: unknowable, unknowing
Mutual synonyms
Related pairs
Both terms in one sentence
- Unknown male vocalists (several vocalists are credited in the liner notes, but it's not known who sang what) sang "Ruthie Rollover", "Chiquito War", and "Beer-Beer-Beer".
Source: Music / Da Yoopers -
It is unknown if this ruined future is the same world as the original TV series or AO's world, and is not known whether did Ao firing the final shot of the Quartz cannon averted this future from happening.
Source: Bad Future -
Their numbers increase as the infestation grows in strength — it's not known whether this is the result of an unknown form of brainwashing or simply a psychological/practical response to the overwhelming Alien Invasion.
Source: Les Collaborateurs
Cite this Source
Unknown and Not known. (2016). Retrieved 2026, July 29, from https://thesaurus.plus/related/not_known/unknown
Not known & Unknown. N.p., 2016. Web. 29 Jul. 2026. <https://thesaurus.plus/related/not_known/unknown>.
Unknown or Not known. 2016. Accessed July 29, 2026. https://thesaurus.plus/related/not_known/unknown.
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