un·cer·tain | \ˌən-ˈsər-tᵊn \

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 \ 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

Augustus didn’t emerge from uncertain beginnings and civil war through kindliness and good deeds; nor did Jahangir win the throne by patience and piety. Maxwell Carter, WSJ, "‘Empress’ Review: Light of the Mughal World," 13 July 2018 The funds to purchase the Russian could be raised by selling Gonzalo Higuain and Daniele Rugani, with both players' futures uncertain with rumours linking the duo with moves away. SI.com, "Cristiano Ronaldo's Juventus Transfer Could Ruin Arsenal & Chelsea's Plans to Sign WC Breakout Star," 13 July 2018 The fate of Russell Crowe’s jockstrap, however, is thus far uncertain. Natasha Bach, Fortune, "Not Even John Oliver Could Save Two of the Last Remaining Blockbusters in the U.S.," 13 July 2018 Contract negotiations between United Steelworkers and ArcelorMittal got off to an uncertain start, with the union saying the international steelmaker is seeking major concessions despite the improved market and economy. Karen Caffarini, Post-Tribune, "NW Indiana steel contract talks start with sides far apart," 13 July 2018 And banks in some countries are still weighed down by bad loans of uncertain quality, making them hard to value as acquisition targets. The Economist, "Why the euro zone hasn’t seen more cross-border bank mergers," 12 July 2018 What exactly happened there remains somewhat uncertain. Gabby Raymond, Time, "The Justice Department Has Reopened Its Investigation of Emmett Till's Murder. Here Are 5 Things to Know About the Case," 12 July 2018 With the news of Supreme Court Justice Anthony Kennedy’s retirement—and President Donald Trump’s pick of Brett Kavanaugh as his nominee for replacement—the fate of reproductive rights is frighteningly uncertain. Lauren Rankin, SELF, "It’s Legal for Crisis Pregnancy Centers in California to Lie to You About Abortion," 11 July 2018 Not 'normal times' But NATO backers acknowledge that positions like those espoused by Desch seem to be closer to the president’s thinking on the uncertain value to the US of a military alliance like NATO. Howard Lafranchi, The Christian Science Monitor, "NATO: Does old squabble over costs mask US shift away from Europe?," 10 July 2018

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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Phrases Related to uncertain

in no uncertain terms

Statistics for uncertain

Last Updated

13 Oct 2018

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 \

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).


lying above or upon

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