UNCERTAIN Synonyms: 104 Similar and Opposite Words

uncertain

adjective

ˌən-ˈsər-tᵊn

Definition of uncertain

as in volatile

likely to change frequently, suddenly, or unexpectedly the stifling heat would occasionally be relieved by an uncertain breeze

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in unsure

not feeling sure about the truth, wisdom, or trustworthiness of someone or something never uncertain of her political beliefs or judgment, she was a decisive and fearless leader

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of uncertain The exact track and strength of the coastal low remain uncertain, and those details will determine just how significant the impacts become. — Grant Gilmore, CBS News, 10 Nov. 2026 Support among incoming governors remains uncertain, and opponents are preparing constitutional challenges that could send the plan to the Supreme Court. — Nicholas Riccardi, Los Angeles Times, 10 Nov. 2026 Last, the study didn’t offer any hints as to how GLP-1 drugs may contribute to NAION—and researchers remain uncertain of a possible mechanism. — Beth Mole, ArsTechnica, 10 Nov. 2026 While acknowledging that Alphabet has other growth drivers, including its fast-growing cloud business, YouTube, and Waymo, Jim is uncertain that those businesses can offset the pressure on search. — Natasha Abellard, CNBC, 9 Nov. 2026 See All Example Sentences for uncertain

Recent Examples of Synonyms for uncertain

Adjective

Technology stocks — a key driver of rallies in recent years — have been notably volatile in 2026.

— Chloe Taylor, CNBC, 11 Nov. 2026
In the case of foods and certain beverages, breakdown of the amino acids results in volatile Strecker aldehydes, which are responsible for aroma, and in aminoketones, which impart flavor and coloration, particularly browning.

— Encyclopedia Britannica, Encyclopedia Britannica, 9 Nov. 2026

Definition of volatile

Adjective

Meanwhile, Corbett is unsure about the future of her space inside the building.

— CBS News, CBS News, 8 Nov. 2026
Trump’s immigration crackdown has put the American dream on hold for aspiring immigrants, who remain unsure whether the election will bring meaningful policy changes.

— Laurie Kellman, Los Angeles Times, 8 Nov. 2026

Definition of unsure

Adjective

Perhaps the arrival of fall and winter, and with it rougher and more unpredictable seas, will reduce the flow.

— Pedro Portal, Miami Herald, 12 Nov. 2026
Potential applications include manufacturing, space exploration and search-and-rescue missions, where robots may need to navigate unpredictable environments, manipulate objects and adapt to changing requirements.

— Jijo Malayil, Interesting Engineering, 12 Nov. 2026

Definition of unpredictable

Adjective

Ivan, the younger son, is doubtful and skeptical of his father, whereas Andrey, the elder, is faithful and trusting—the twin archetypes of man’s relation to the divine.

— Joshua Yaffa, New Yorker, 2 Nov. 2026
He has been joined in recent years by tax-skeptical scholars at the Manhattan Institute and Tax Foundation.

— M. Nolan Gray, Washington Post, 2 Nov. 2026

Definition of skeptical

Adjective

Rigorous, blustery winter; winding sleety spring; hot, moist enervating summer; changeful autumn with its dog-days; these are absolutely unknown.

— San Diego Union-Tribune, San Diego Union-Tribune, 1 Jan. 2023
Hers is the kind of face that inspires directors to tight framing — gleaming, as if smoothed from marble, and yet somehow pliant, changeful.

— Jordan Kisner Jack Davison, New York Times, 11 Oct. 2022

Definition of changeful

Adjective

The glow of many Turners has dwindled, thanks to unstable pigments, but here is an immaculate exception.

— Anthony Lane, New Yorker, 5 Nov. 2026
And while unstable coalitions repeatedly fused and dissolved in the halls of power, outside these halls pipes burst and roads crumbled.

— Ryan Lenora Brown, Christian Science Monitor, 5 Nov. 2026