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

Relevance

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 What remains uncertain A campaign at the lunar South Pole would need to run for months, and no robot team has yet worked that hard, for that long, that far from help. — Wanjiku Chebet Kanjumba, The Conversation, 13 Aug. 2026 Whether homeowners will suddenly stop earning interest on their escrow account is uncertain, Maman said. — Sarah Agostino, CNBC, 13 Aug. 2026 Towards the end there’s a dreamlike montage of uncertain efficacy, though stunning images of Toni and young Adela on a bed covered in vines and grasses are so mesmerizing that the eye wants to linger further. — Jay Weissberg, Variety, 13 Aug. 2026 For parents already uncertain about vaccination, those signals matter. — Krutika Kuppalli, STAT, 13 Aug. 2026 See All Example Sentences for uncertain

Recent Examples of Synonyms for uncertain

Adjective

Back in the early 1980s, amid a volatile chicken market, McDonald’s needed help pricing their nuggets and limiting the risk of menu price fluctuations.

— Sarah Glodek, Fortune, 14 Aug. 2026
Historically, memory has been a volatile, highly cyclical industry.

— Jeff Kilburg, CNBC, 14 Aug. 2026

Definition of volatile

Adjective

Some have been Ukrainian drones knocked off course by Russian electronic warfare, such as the jamming of navigation signals, which can make their flight paths unpredictable and complicate decisions about whether and where to shoot them down.

— Elsa Ohlen, CNBC, 14 Aug. 2026
Carefully evaluate both options, then, before making a final decision and don't discount the advantages of splitting your funds between both account types, which may be your best recourse in today's still uneven and unpredictable economic terrain.

— Matt Richardson, CBS News, 13 Aug. 2026

Definition of unpredictable

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

Maybe someone noticed a person acting suspicious, heard a fight, saw someone leaving the area or remembers a detail that seemed insignificant at the time.

— Simcha Itzkowitz, New York Daily News, 12 Aug. 2026
CyberGuy's guide to protecting yourself from social media scammers includes more ways to evaluate suspicious accounts.

— Kurt Knutsson, FOXNews.com, 12 Aug. 2026

Definition of suspicious

Adjective

No one sees exactly what happened, and the only witness, a mentally unstable man, gives conflicting accounts that deepen the uncertainty.

— Georg Szalai, HollywoodReporter, 10 Aug. 2026
Events plod forward, one after the other, and although Michael Shaeffer is a thoroughly compelling presence as the cruel and chronically unstable monarch Aerys, other performances seem nuance-free.

— Andreas Wiseman, Deadline, 10 Aug. 2026