UNCHALLENGEABLE Synonyms: 57 Similar and Opposite Words

unchallengeable

adjective

ˌən-ˈcha-lən-jə-bəl

Definition of unchallengeable

as in unquestionable

not capable of being challenged or proved wrong the contention that there are certain unchallengeable rules governing proper grammar

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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 unchallengeable Without spoiling the big second-act reveal, no one in this play – or in the audience – has an unchallengeable claim on the truth. — Greg Evans, Deadline, 18 Oct. 2026 Californians have been conditioned to consider recycling to be an unchallengeable proposition. — Kerry Jackson, Oc Register, 4 Feb. 2026 The lens of the hearing never focused on Robeson, who was seen as only a prop for Robinson’s patriotism, unworthy of rediscovery, especially as the Robinson/Rickey integration story—sports as the pathway to equality—became virtually unchallengeable. — Literary Hub, 21 Jan. 2026 Regular board and executive succession planning, with a balance of independent directors, can ensure the right questions are asked and no single person becomes unchallengeable. — James Henderson, Forbes, 4 Dec. 2024 No longer having to play cosmetic chemist is an unchallengeable win. — Essence, 23 Oct. 2023 This was rooted in a calculation that America’s greatest source of strength was global perceptions of the country as unchallengeable. — Max Fisher, New York Times, 18 Mar. 2023 In the heady days after the Cold War, the order appeared both unchallenged and unchallengeable. — Ivo Daalder, Foreign Affairs, 21 June 2022

Recent Examples of Synonyms for unchallengeable

Adjective

Throughout her career, the fan trust, touring equity and longevity were unquestionable.

— Carl Lamarre, Billboard, 5 Oct. 2026
That was the unquestionable trend that emerged from Milan Fashion Week for spring 2027, and retailers could not get enough of them, praising Prada‘s offer that focused on the singular garment and its versatility.

— Samantha Conti, Footwear News, 28 Sep. 2026

Definition of unquestionable

Adjective

These are not partisan or risible statements, but indisputable.

— Gerry Shih, Washington Post, 17 Oct. 2026
Much has been made of Winter’s idiosyncratic star power, and as an extremely tall, wet-dog-handsome instrumental virtuoso with a one-of-a-kind voice and just enough self-aware wit and lacerating lyricism to keep it relatable, that’s indisputable.

— Los Angeles Times, Los Angeles Times, 16 Oct. 2026

Definition of indisputable

Adjective

Funnyman, vulgarian, auteur — Mel Brooks’s imprint on American cinema is incontestable yet scandalously undervalued.

— Manohla Dargis, New York Times, 26 June 2026
The mark was federally registered in 2015 and has since achieved incontestable status, a legal designation that strengthens ownership rights.

— Bryan West, USA Today, 30 Mar. 2026

Definition of incontestable

Adjective

Public health officials say there is no conclusive scientific evidence that supports using cat’s claw for any health purposes.

— Karen Garcia, Los Angeles Times, 23 Oct. 2026
Although the possibility that better sleep could reduce opioid use after surgery is promising, Amaya cautioned that the findings are not conclusive.

— Angelica Stabile, FOXNews.com, 23 Oct. 2026

Definition of conclusive

Adjective

And through the former player's testimony on Friday, the attorneys for Vaccaro have not yet produced incontrovertible evidence of physical violence by Hill against their client.

— Armando Salguero OutKick, FOXNews.com, 9 Oct. 2026
To some, the attack fulfilled long-term right-wing warnings that Israel’s withdrawal from Gaza would yield disaster; and the attack was incontrovertible proof that Palestinians will never live in peace with Israel.

— Dahlia Scheindlin, Time, 7 Oct. 2026

Definition of incontrovertible

Adjective

As a result, mathematical truths do not make up a unified whole of equally indubitable truths; instead, their status as knowledge varies gradually from doubtless facts to increasingly uncertain hypotheses.

— Quanta Magazine, Quanta Magazine, 18 May 2026
The second route, and the route that makes indubitable sense, entails using the techniques and methods of psychology to gauge the performance of AI.

— Lance Eliot, Forbes.com, 15 Apr. 2026

Definition of indubitable

Browse Nearby Words

unchains

unchallengeable

unchallenged

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“Unchallengeable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unchallengeable. Accessed 27 Oct. 2026.

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Synonyms of unchallengeable

adjective

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