UNSOUND Synonyms: 298 Similar and Opposite Words

unsound

adjective

ˌən-ˈsau̇nd

Definition of unsound

as in sick

temporarily suffering from a disorder of the body an unsound horse that will have to be disqualified from the race

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Antonyms & Near Antonyms

as in unreasonable

not using or following good reasoning it is clearly unsound to argue that just because a scientific explanation for that phenomenon does not currently exist, no such explanation is possible

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Antonyms & Near Antonyms

as in insane

unable to think in a clear or sensible way disgruntled relatives tried to prove that the woman was of unsound mind when she made her will

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Antonyms & Near Antonyms

as in erroneous

not being in agreement with what is true an unsound and pernicious stereotype

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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 unsound Because his stance on climate change conflicts with overwhelming scientific consensus, the president has removed climate information from federal websites, approved scientifically unsound reports that favor fossil fuels, and gutted key scientific agencies and boards. — Joseph Bonasia, The Orlando Sentinel, 15 May 2026 Denials based on unwritten or misapplied rules or standards, or perhaps on subjective personal preferences, would be on unsound standing. — Nicole R. Kurtz, Miami Herald, 7 May 2026 What becomes alarmingly evident through the key assumptions check is how many of the current responses expect a quick resolution of the conflict — a supposition that is unsound, or at least unsupported. — Judd Devermont, semafor.com, 27 Apr. 2026 The logic behind Liam Rosenior’s shift to a back five at Brighton & Hove Albion on Tuesday was not entirely unsound. — Conor O'Neill, New York Times, 22 Apr. 2026 See All Example Sentences for unsound

Recent Examples of Synonyms for unsound

Adjective

Grape expectations In 2020, macaques in an enclosure at the sanctuary started getting sick with an HIV-like virus called SRV.

— Jonathan Lambert, NPR, 23 Oct. 2026
Or calling in sick from work even when the doctor cleared you to return in the new year.

— Literary Hub, Literary Hub, 23 Oct. 2026

Definition of sick

Adjective

On the surface, paying as low as 24 cents for an hour of streaming game time doesn’t sound completely unreasonable.

— Kyle Orland, ArsTechnica, 21 Oct. 2026
If Putin rejects the framework — or, more likely, demands unreasonable changes — then the world will at least know who blocked the fledgling peace effort.

— David Ignatius, Washington Post, 21 Oct. 2026

Definition of unreasonable

Adjective

Bisignano, a former Wall Street CEO who has been overhauling how the agency operates, also said SSA was working to fix erroneous records.

— Fernanda Tronco, Fortune, 20 Oct. 2026
In his own review of the case, Mandell failed to flag an erroneous jury instruction that four years later would lead to the conviction being overturned.

— Samantha Melamed, ProPublica, 13 Oct. 2026

Definition of erroneous

Adjective

For however poorly things are going — and the bad tone set by the starters has leaked into some defensive lapses and some pressing at the plate — the Padres got themselves into a really favorable position before this.

— Kevin Acee, San Diego Union-Tribune, 4 Sep. 2025
This involves having a poorly or non-functioning colon and is not usually reversible.

— Dr. John De Jong, Boston Herald, 17 Aug. 2025

Definition of poorly

Adjective

Giving any person a $100 million contract to coach a college athletic team is irrational.

— Letters to the Editor, The Orlando Sentinel, 28 Oct. 2026
The industrial revolutions of the past produced enormous value alongside bankruptcies, dislocations, and periods of irrational exuberance.

— Brian Solis, Forbes.com, 5 Oct. 2026

Definition of irrational

Adjective

Unfortunately, his doctor interprets all the screaming about an alien presence in Thomas’ head as a garden-variety psychotic breakdown, and remands him to a more secure facility.

— Tasha Robinson, Vulture, 14 Oct. 2026
It may also be used to treat certain other psychotic conditions, such as psychosis arising in Parkinson disease.

— Encyclopedia Britannica, Encyclopedia Britannica, 7 Oct. 2026

Definition of psychotic

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unsought

unsound

unsoundness

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“Unsound.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsound. Accessed 28 Oct. 2026.

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Synonyms of unsound

adjective

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