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 Several additional rounds of showers and storms are possible next week, but the timing is very uncertain. — Joseph Dames, CBS News, 27 Aug. 2026 The mock draft assumes a scenario where the Dolphins are bad enough with Willis behind center in 2026, but still either pleased with his play or at least uncertain about him after one season. — David Furones, Sun Sentinel, 27 Aug. 2026 However, Hardy’s outlook for the 2026 season is somewhat uncertain after he was shot in the leg at a concert in May. — Dane Brugler, New York Times, 26 Aug. 2026 Despite the Cuthberts’ eye-rolling, the book itself seems uncertain. — Literary Hub, 26 Aug. 2026 See All Example Sentences for uncertain

Recent Examples of Synonyms for uncertain

Adjective

One wild card for inflation has been oil prices, which have been volatile due to uncertainty about the war in Iran.

— ABC News, ABC News, 28 Aug. 2026
Citadel’s stock transactions are giving investors a glimpse of how Griffin is navigating an increasingly volatile market.

— Miami Herald, Miami Herald, 28 Aug. 2026

Definition of volatile

Adjective

Margarita, who studied jewelry design, is unsure whether Princess Margaret would have been a fan of her jewelry preferences.

— Bailey Bujnosek, InStyle, 1 Sep. 2026
For the first ten minutes, the audience seems a little unsure where any of this is going — something Lyons is self-aware enough to address.

— Rebecca Rosman, NPR, 31 Aug. 2026

Definition of unsure

Adjective

Researchers from Tohoku University in Japan and VISTEC in Thailand say the approach could help robots move more effectively through unpredictable terrain.

— Jijo Malayil, Interesting Engineering, 28 Aug. 2026
Prolific and versatile, Richard Linklater has been one of the most joyously unpredictable filmmakers for more than 35 years.

— Mark Olsen, Los Angeles Times, 27 Aug. 2026

Definition of unpredictable

Adjective

And given their preference for rocky environments over sandy lagoons and the crabs’ reproductive prowess, fishermen and experts alike are skeptical.

— ABC News, ABC News, 2 Sep. 2026
The early sales reps who thrived on instinct and relationships start selling into a market that’s crowded, educated and skeptical.

— Doug May, Forbes.com, 2 Sep. 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

Glendale police received multiple calls about a suspicious male adult, with officers first responding to a retail store in the 1500 block of Glenoaks Boulevard.

— Andrew J. Campa, Los Angeles Times, 2 Sep. 2026
By the time something appears suspicious, causality is fragmented across systems, logs and identities.

— Brian Contos, Forbes.com, 2 Sep. 2026

Definition of suspicious

Adjective

Risk assessments should examine where a river bends, where slopes are unstable and where a single failure could cut off several communities.

— Victoria Milko, Fortune, 31 Aug. 2026
Significant political risk remains due to Venezuela's unstable government and historical tendency to renege on oil agreements.

— Michael Lynch, Forbes.com, 30 Aug. 2026

Definition of unstable

Adjective

The lawsuit says the decision was unlawful, unsupported by facts and inconsistent with the military’s past praise of Claude.

— Reuters, NBC news, 28 Aug. 2026
As a brief respite, the silly friend in your group chat, who keeps violently inconsistent hours, has shared something that will probably not break your heart, which seems as worthy an offering as any.

— Hanif Abdurraqib, New Yorker, 28 Aug. 2026