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

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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

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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 But no peace talks are being conducted, leaving uncertain when the conflict will be resolved. — Bart Jansen, USA Today, 3 Sep. 2026 The psychological thriller, which Zeller wrote, produced and directed, follows the emotional and moral challenges faced by a couple in an increasingly uncertain world. — Diana Lodderhose, Deadline, 2 Sep. 2026 The shift toward electric vehicles has left internal combustion engines facing an uncertain future. — Mrigakshi Dixit, Interesting Engineering, 2 Sep. 2026 Also in Shanghai, and increasingly elsewhere, brands continue to favor the slow pop-up model over a long-term real estate commitment due to not only the uncertain outlook, but the incredibly fast churn of market trends. — Denni Hu, Footwear News, 1 Sep. 2026 See All Example Sentences for uncertain

Recent Examples of Synonyms for uncertain

Adjective

Dado Ruvic | Reuters Bitcoin headed for its third straight winning week, as traders searched for refuge amid volatile moves in equities, currencies and bond markets.

— Liz Napolitano, CNBC, 4 Sep. 2026
That meant trade reporting on the tape often ran late, sometimes hours late during a volatile market or big sell-off.

— Brian Lund, Encyclopedia Britannica, 4 Sep. 2026

Definition of volatile

Adjective

Researchers are also still unsure which spacecraft burn up completely and how many fragments may reach the ground, putting lives and property at risk.

— Tereza Pultarova, Space.com, 8 Sep. 2026
Police and lifeguards were unsure as to the most recent jumping fatality, with one official pointing to the 2019 death of 15-year-old Anthony Womack, a National City resident.

— Andrew J. Campa, Los Angeles Times, 8 Sep. 2026

Definition of unsure

Adjective

Initially skeptical of the tub, her contractors took pride in the end result.

— Sean Santiago, Architectural Digest, 9 Sep. 2026
El Sayed has been skeptical of AI throughout his Senate campaign against GOP candidate Mike Rogers, calling for government ownership of the technology and backing a sweeping tax on AI companies’ stock.

— Emily Hallas, The Washington Examiner, 9 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

Interior Secretary Jonvic Remulla, who accompanied the national police chief in serving the warrant to Romualdez, said he was admitted to a Manila hospital Monday afternoon due to unstable blood pressure and anxiety attack.

— ABC News, ABC News, 7 Sep. 2026
As Anna covers for Fyodor’s addiction and increasingly unstable professional behavior, her devotion starts to look poisonous for them both.

— Alison Foreman, IndieWire, 5 Sep. 2026

Definition of unstable

Adjective

Von Arx, one of the researchers, said the behavior appeared inconsistent with what OpenAI would intentionally want its agents to do.

— Aamir Khollam, Interesting Engineering, 4 Sep. 2026
Authorities stopped vehicles owned by Metur associates 14 times in the back half of August, with reviews of drivers' documents that lasted up to an hour, van Duijnhoven said, and punishments that were inconsistent and severe.

— ABC News, ABC News, 4 Sep. 2026