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

Synonyms & Similar Words

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 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 This not only makes the shade problem worse, Chamberlain says, but makes the tree more structurally unsound and vulnerable to damage in harsh weather conditions. — Peg Aloi, The Spruce, 30 Mar. 2026 See All Example Sentences for unsound

Recent Examples of Synonyms for unsound

Adjective

Some recalls, Eskin said, are made after companies’ routine testing catches a pathogen before anyone gets sick, while others involve outbreaks that are already underway and vary widely in size and severity.

— Dian Zhang, USA Today, 28 Aug. 2026
Sanchez also ordered a meal from Taco Bell, but didn’t get sick.

— Rebecca Johnson, Chicago Tribune, 28 Aug. 2026

Definition of sick

Adjective

The new season has been absolutely insane through four episodes as the hunt to save Joe (Zoe Saldaña) from her kidnappers is underway.

— David Hookstead OutKick, FOXNews.com, 25 Aug. 2026
If Gigi is malintentioned and insane and a homewrecker, there’s no story, right?

— Hilary Lewis, HollywoodReporter, 25 Aug. 2026

Definition of insane

Adjective

Towers told ProPublica that the audit had reached erroneous conclusions, that the auditors did not give him the opportunity to fully defend his work and that the journal’s willingness to stand by the study is proof that his research is sound.

— Amy Yurkanin, ProPublica, 24 Aug. 2026
For example, antiquarian scholars introduced the erroneous notion that druids built stone circles—most notably Stonehenge—for their ceremonies, an idea that became embedded in the popular imagination during the 18th century.

— Encyclopedia Britannica, Encyclopedia Britannica, 14 Aug. 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

But the question remained unsolved for polygons with irrational angles.

— Sam Macdonald, Scientific American, 14 Aug. 2026
As a result, the argument goes, today's spending is irrational because the hardware would need to be replaced too frequently to generate an attractive return on investment, known as ROI.

— , CNBC, 12 Aug. 2026

Definition of irrational

Adjective

But a poor reaction to her recovery medication kicked off a psychotic episode.

— CT Jones, Rolling Stone, 26 Aug. 2026
Psychiatric disorders are generally divided into mood disorders and psychotic disorders, Osborne said; postpartum psychosis is a mood disorder, in which mood symptoms accompany psychotic symptoms.

— Jen Christensen, CNN Money, 13 Aug. 2026

Definition of psychotic

Adjective

Travelers can place too much trust in a confident but inaccurate answer.

— Jeff Fromm, Forbes.com, 28 Aug. 2026
Viral posts outlining ways to find AI tool hacks are now commonplace, but this also means an increase in factually inaccurate claims that are seen by millions of people.

— James Peckham, PC Magazine, 27 Aug. 2026

Definition of inaccurate

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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 2 Sep. 2026.

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Synonyms of unsound

adjective

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