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 future of college hockey in Alaska already is uncertain, especially with the two schools facing a new wave of budget cuts that were also announced last week. Randy Johnson, Anchorage Daily News, "WCHA’s demise stems from geography, struggling programs," 4 July 2019 Yet Hampshire, uncertain what its short-term future held, only admitted individuals who had applied early decision or taken a gap year. Alison Kuznitz, BostonGlobe.com, "Amid turmoil at Hampshire College, just 15 take the leap to join freshman class," 30 June 2019 Fury’s uncertain vision isn’t the only mistake on Marvel’s recent movie posters. Colleen Cronin, PEOPLE.com, "Marvel's Samuel L. Jackson Outraged Over New Spider-Man: Far From Home Poster Error," 24 June 2019 If uncertain, fall back on what has worked in the past. Tribune Content Agency, oregonlive.com, "Horoscope for June 24, 2019: Gemini, consider the source; Virgo, make them an offer they can’t refuse," 24 June 2019 But thanks to the uncertain, tight-lipped Donna, Sophie has never known his identity. Gary Goldstein, latimes.com, "Review: ‘Mamma Mia!’ with an Asian cast? Gimme! Gimme! Gimme!," 12 June 2019 But the outcome of those talks is uncertain, reflected in recent volatility in the U.S. soy futures market. Anatoly Kurmanaev, WSJ, "A Surprise Winner From the U.S.-China Trade Spat: Russian Soybean Farmers," 21 Feb. 2019 Theresa May’s leadership is uncertain, and the future of the United Kingdom is in question, leaving its population polarized. Elise Taylor, Vogue, "Queen Elizabeth Just Made a Powerful Statement for a Troubled Time," 25 Jan. 2019 While the new guidelines are still uncertain, always keep a close eye on your child when changing them and to never leave children unattended on a changing table or mat. Lindsey Murray, Good Housekeeping, "New Safety Standards Are Coming for Baby Changing Products — Here's Everything You Need to Know," 25 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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Statistics for uncertain

Last Updated

7 Jul 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

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