Definition of uncertain
1a : not known beyond doubt : dubious an uncertain claim
b : not having certain knowledge : doubtful remains uncertain about her plans
c : not clearly identified or defined
a fire of uncertain origin
3 : indefinite, indeterminate the time of departure is uncertain
4 : not certain to occur : problematical his success was uncertain
5 : not reliable : untrustworthy an uncertain ally
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Time Traveler for uncertain
The first known use of uncertain was in the 14th century
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