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

But the industry faces an uncertain future as cheaper forms of power, such as natural gas and renewable energy, eat away at its market share. The Washington Post, The Mercury News, "Biden jumps on the Green New Deal train with climate plan," 4 June 2019 Durant, the two-time NBA Finals MVP who was averaging more than 34 points during the playoffs, remains out with a sore right calf and his return is uncertain. Anne M. Peterson, The Seattle Times, "Green, Warriors beat Blazers for 3-0 lead in West finals," 19 May 2019 Manufacturing activity in the world’s two largest economies perked up in March, an antidote to financial-market fears of a coming global recession, though pockets of weakness remain and the outlook is uncertain. Paul Hannon, WSJ, "U.S. and Chinese Manufacturing Stabilize, While Europe Lags Behind," 1 Apr. 2019 Guy injured his ankle in the first half and his return was uncertain. Gary B. Graves, The Seattle Times, "Virginia shakes off Purdue 80-75 in OT to win South Region," 31 Mar. 2019 Some of the Hallmark series’ stars, like Pascale Hutton and Paul Greene have spoken out, reminding Hearties to remain calm during this uncertain time. Megan Stein, Country Living, "A 'When Calls the Heart' Star Says He's 'Totally in the Dark' About Show's Return," 7 Apr. 2019 In striving to provide the best service for his customers, Soleimani realized that many of them are uncertain when making big design decisions. Hadley Keller, House Beautiful, "This Company Lets You Try Rugs Before You Buy Them," 5 Apr. 2019 The Reserve Bank of New Zealand kept interest rates on hold at a policy meeting on Wednesday, but warned the next move in interest rates was more likely to be down given an increasingly uncertain global economy. James Glynn, WSJ, "RBNZ Adopts Dovish Outlook Fearing Global Downturn," 26 Mar. 2019 In the latest promo, Beth and Randall are fighting and their future together looks uncertain. Kayla Keegan, Good Housekeeping, "This Is Us’s Emotional Promo for Next Week Has Everyone Worked Up Over Randall and Beth," 20 Mar. 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

9 Jun 2019

Look-up Popularity

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).


incapable of being surmounted or overcome

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