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 With the election still half a year away and its outcome is still highly uncertain, Trump is a long way from office. Adam Taylor, Washington Post, 21 Mar. 2024 The trajectory of our own life is uncertain, but a celestial alignment is a sure thing, as unstoppable as time itself. Marina Koren, The Atlantic, 21 Mar. 2024 California high schools offering data science classes — about 435 across the state — are also uncertain over how to revise curriculum and counsel their students. Teresa Watanabe, Los Angeles Times, 19 Mar. 2024 Even Boeing seems uncertain when the planes will be ready as an army of US inspectors sift through its factories, meaning the company can’t make any firm predictions when things might return to normal. Anthony Palazzo, Fortune, 18 Mar. 2024 With Conforto’s status beyond this season uncertain, the streak could reach 19 in 2025. Evan Webeck, The Mercury News, 16 Mar. 2024 More people were searching for reliable information because the situation was so uncertain. Chris Mueller, USA TODAY, 15 Mar. 2024 The Detroit Department of Transportation driver died a short time later, in early April 2020, but the message in his video, pushing driver safety, resonated with a worried and uncertain public. Eric D. Lawrence, Detroit Free Press, 15 Mar. 2024 The brother of Stefanie Smith — the 41-year-old woman who suddenly died after falling ill on an American Airlines flight from the Dominican Republic last week — shares how the family is still uncertain about what caused her death. Charna Flam, Peoplemag, 9 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'uncertain.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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

Dictionary Entries Near uncertain

Cite this Entry

“Uncertain.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/uncertain. Accessed 29 Mar. 2024.

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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