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

The goats’ dire situation first came to light when a former dairy employee raised concerns after witnessing emaciated and sick animals on the property, the former employee told the Idaho Statesman last year.

— Sally Krutzig, Idaho Statesman, 16 Oct. 2026
What’s interesting is that Conan Doyle got sick of writing Sherlock Holmes.

— Jesse Whittock, Deadline, 16 Oct. 2026

Definition of sick

Adjective

But Michael Edney, who worked at the OLC under Bush, said the opinion’s reading of executive privilege was not unreasonable, given the importance that some presidents place on outside consultation.

— Perry Stein, Washington Post, 18 Oct. 2026
Both sides have accused each other of being unreasonable and of ignoring practical concerns about voting and election security, though in very different ways.

— Kevin Rector, Los Angeles Times, 17 Oct. 2026

Definition of unreasonable

Adjective

First and foremost, as a homeowner myself the property taxes are insane and continue to go up.

— Stephen Korka, Sun Sentinel, 13 Oct. 2026
That may be the name of her next album, but Venus’ insane popularity also speaks to the way Metropia is moving forward, constantly looking for the next shiny thing.

— Kate Erbland, IndieWire, 10 Oct. 2026

Definition of insane

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

The industrial revolutions of the past produced enormous value alongside bankruptcies, dislocations, and periods of irrational exuberance.

— Brian Solis, Forbes.com, 5 Oct. 2026
If anyone can reconstruct Apéry’s reasoning, the odd values of zeta may finally be proven irrational.

— Lyndie Chiou, Scientific American, 2 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

Adjective

Medical identity theft can lead to fraudulent bills and inaccurate patient records, so catching problems early is important.

— Kurt Knutsson, FOXNews.com, 18 Oct. 2026
Working with fellow researchers, Cade now has a good reason to believe the Nature report is more than likely inaccurate – the train’s rail route didn’t exist until 1846.

— Mike McRae October 15, New Atlas, 16 Oct. 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 22 Oct. 2026.

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Synonyms of unsound

adjective

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