uncertain

adjective

un·​cer·​tain ˌən-ˈsər-tᵊn How to pronounce uncertain (audio)
1
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
2
: not constant : variable, fitful
an uncertain breeze
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
uncertainly adverb
uncertainness 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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This phenomenon has been further propelled by ongoing inflation, high interest rates, and an uncertain economic outlook. Trefis Team, Forbes.com, 20 May 2025 In the early, uncertain days of COVID-19, when people were told to stay home to save lives, Lightfoot chose compassion over citations. The Editorial Board, Chicago Tribune, 20 May 2025 That example helps to prove that not all uncertain situations can be linked to being in the trenches — Carson last got a game over three years ago anyway and is essentially in the squad these days for (very valuable) morale purposes. Sam Lee, New York Times, 19 May 2025 No shock, no blowout Walmart’s strong Q1 performance this year was driven by modest digital growth and grocery share gains, especially from higher-income shoppers trading down in an uncertain economy. Catherine Baab, Quartz, 19 May 2025 See All Example Sentences for uncertain

Word History

First Known Use

14th century, in the meaning defined at sense 3

Time Traveler
The first known use of uncertain was in the 14th century

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Cite this Entry

“Uncertain.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/uncertain. Accessed 23 May. 2025.

Kids Definition

uncertain

adjective
un·​cer·​tain ˌən-ˈsərt-ᵊn How to pronounce uncertain (audio)
ˈən-
1
: not definite or fixed
an uncertain quantity
2
a
: not sure
uncertain of the truth
b
: not known for sure
an uncertain claim
3
: likely to change : not dependable
uncertain weather
uncertainly adverb

More from Merriam-Webster on uncertain

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