un·​cer·​tain | \ ˌən-ˈsər-tᵊn How to pronounce uncertain (audio) \

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
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

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Other Words from uncertain

uncertainly adverb
uncertainness \ ˌən-​ˈsər-​tᵊn-​(n)əs How to pronounce uncertainness (audio) \ 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.
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Recent Examples on the Web

Among the big issues hurting business confidence are political standoffs such as the trade war and Britain’s uncertain exit from the European Union. Washington Post, "Europe eyes stimulus plan, but ultra-low rates raise doubts," 11 Sep. 2019 Left guard Pat Elflein missed practice Wednesday because of a knee injury, and his status is uncertain for Sunday’s game at Green Bay. Chris Tomasson, Twin Cities, "Influenced by Anthony Barr’s move, lineman Dakota Dozier left Jets to sign with Vikings," 11 Sep. 2019 As the players quickly dressed and left the park, Cora stayed behind deep into the night discussing the now uncertain state of the team with a friend. BostonGlobe.com, "He joined team president Sam Kennedy, chief operating officer Jon Gilula, and human resources director Amy Waryas for a ceremony honoring a group of longtime employees.," 10 Sep. 2019 Experts at the National Hurricane Center gives a disturbance making its way into the Gulf of Mexico a fighting 30 percent chance of developing into something bigger by the weekend, although its path is uncertain at this point. Jay R. Jordan, Houston Chronicle, "Daily showers, high temps in store for Houston this week," 10 Sep. 2019 His role with New England was also uncertain because of Brown’s arrival. Dennis Waszak Jr., The Denver Post, "Jets acquire WR Demaryius Thomas from Patriots for draft pick, AP sources say," 10 Sep. 2019 Sawyer returned to work sooner than expected, but the ensuing months are more uncertain. Chabeli Herrera, orlandosentinel.com, "After Hurricane Dorian, the Bahamas prepares for another hit — to its crucial tourism industry," 8 Sep. 2019 Also uncertain, Sanford concedes, are the number of Republicans willing to abandon Mr. Trump. Caitlin Conant, CBS News, "2020 Sunday Trail Markers: Get ready for a major week in politics," 8 Sep. 2019 For the most part, the panel was uncertain on the exact impact on such issues. Ana Ceballos, sun-sentinel.com, "Florida assault weapons registry would come at a $4 million cost," 3 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'uncertain.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of uncertain

14th century, in the meaning defined at sense 3

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Statistics for uncertain

Last Updated

15 Sep 2019

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Time Traveler for uncertain

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

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More Definitions for uncertain



English Language Learners Definition of uncertain

: not exactly known or decided : not definite or fixed
: not sure : having some doubt about something
: not definitely known


un·​cer·​tain | \ ˌən-ˈsər-tᵊn How to pronounce uncertain (audio) \

Kids Definition of uncertain

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

Other Words from uncertain

uncertainly adverb

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Comments on uncertain

What made you want to look up uncertain? Please tell us where you read or heard it (including the quote, if possible).


miscellaneous remnants or debris

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