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

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Recent Examples of uncertain Companion features that simulate romance, intimacy, or devotion should be disabled for minors and limited by default when age is uncertain. — Ryan McBain, STAT, 2 July 2026 In the oral arguments, conservative Supreme Court justices asked about the possibility of grace periods making an election’s outcome uncertain for weeks or months. — Jamie Rowen, The Conversation, 2 July 2026 Harvard Health has taken a critical look at Apollo Neuro, and Medscape has warned about uncertain efficacy in at-home vagus stimulation devices. — Samantha Agate, Charlotte Observer, 3 July 2026 Harvard Health has published a critical take on Apollo Neuro, and Medscape has cautioned about at-home vagus nerve stimulation devices, warning of uncertain efficacy and safety. — Samantha Agate, Kansas City Star, 2 July 2026 See All Example Sentences for uncertain

Recent Examples of Synonyms for uncertain

Adjective

Related Stories Set in 1948 Malaya in the volatile years that followed the end of World War II, the film traces a Malay soldier and a British soldier who are left behind after the British military withdraws.

— Naman Ramachandran, Variety, 3 July 2026
While the rally continued into early 2026, trade soon turned volatile.

— Chloe Taylor, CNBC, 3 July 2026

Definition of volatile

Adjective

Essentially, markets believe that interest rates will rise in 2026 but are unsure of both the magnitude and timing.

— Simon Moore, Forbes.com, 7 July 2026
Engineers are unsure of the condition of Swift’s thermal insulation, and ground controllers will take a cautious approach to determining where and when Link’s robotic arms can capture the satellite.

— Stephen Clark, ArsTechnica, 6 July 2026

Definition of unsure

Adjective

Deeply skeptical of his diplomatic attempts with Iran, Prime Minister Benjamin Netanyahu could view the president’s comments as an opening to continue operations both in Lebanon, against Hezbollah, or in Iran itself.

— Ivana Kottasová, CNN Money, 8 July 2026
As recently as last year, the bank’s executives were skeptical that ventures known for such voracious capital spending would be able to sustain their business models.

— Bloomberg, Mercury News, 8 July 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

Nile finds himself in a cat-and-mouse dynamic with his new neighbor (Claire Danes), an author in search of her next book subject who is suspicious of his innocence.

— Senior Television, Los Angeles Times, 8 July 2026
But by playing coy about next steps, Hamas has given observers and critics plenty of reasons to be suspicious about this latest development.

— Rafi Schwartz, TheWeek, 8 July 2026

Definition of suspicious

Adjective

Relying on hand tools instead of heavy machinery, firefighters tunneled through unstable debris to rescue a security guard trapped for eight days.

— Mery Mogollón, Los Angeles Times, 5 July 2026
In an unstable industry with IP, nepotism and maybe even now artificial intelligence ruling supreme, Ridd and Boa have doubled down on emerging filmmakers with original stories.

— Lily Ford, HollywoodReporter, 2 July 2026