Definition of uncertain
2 : not certain to occur : problematical <his success was uncertain>
3 : not reliable : untrustworthy <an uncertain ally>
4 a : 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>
uncertainnessplay \-tən-(n)əs\ noun
Examples of uncertain in a sentence
The time of departure is still uncertain.
We are still uncertain of the truth.
She remains uncertain about her plans.
I'm uncertain about how to respond.
The cause of the fire is uncertain.
He has an uncertain temper.
They face a financially uncertain future.
First Known Use of uncertain
UNCERTAIN Defined for English Language Learners
Definition of uncertain for English Language Learners
: not exactly known or decided : not definite or fixed
: not sure : having some doubt about something
: not definitely known
UNCERTAIN Defined for Kids
Definition of uncertain for Students
1 : not exactly known or decided on <an uncertain amount>
2 : not sure <They were uncertain of the rules.>
3 : not known for sure <an uncertain claim>
4 : likely to change : not dependable <uncertain weather>
Seen and Heard
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