unsound

adjective

un·​sound ˌən-ˈsau̇nd How to pronounce unsound (audio)
Synonyms of unsoundnext
: not sound: such as
a
: not healthy or whole
an unsound horse
b
: not mentally normal : not wholly sane
of unsound mind
c
: not firmly made, placed, or fixed
structurally unsound
d
: not valid or true : invalid, specious
unsound beliefs
unsoundly
ˌən-ˈsau̇n(d)-lē How to pronounce unsound (audio)
adverb

Synonyms of unsound

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Examples of unsound in a Sentence

The roof is structurally unsound. disgruntled relatives tried to prove that the woman was of unsound mind when she made her will
Recent Examples on the Web
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.
Monetary policy appears to have been slow to respond, late — and therefore (perhaps) unsound. — George Calhoun, Fortune, 29 Aug. 2026 Empire Towers remains structurally unsound after construction work caused the building's floor to shift on Thursday. — Mike Hellgren, CBS News, 12 July 2026 None of this sounds basically unsound. — Erik Sherman, Forbes.com, 20 June 2026 Public schools have always been the one institution that has no option but to work through both sound and unsound choices of our society and our leaders. — Baltimore Sun Staff, Baltimore Sun, 20 May 2026 See All Example Sentences for unsound

Word History

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of unsound was in the 14th century

Phrases Containing unsound

Rhymes for unsound

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Browse Nearby Words

unsoul
unsound
unsoundable
See all Nearby Words

Cite this Entry

“Unsound.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsound. Accessed 4 Sep. 2026.

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Kids Definition

unsound

adjective
un·​sound ˌən-ˈsau̇nd How to pronounce unsound (audio)
ˈən-
1
: not healthy or whole
an unsound horse
2
: not mentally normal : not wholly sane
of unsound mind
3
: not firmly made, placed, or fixed
an unsound structure
4
: not based on truth or logic
unsound arguments
unsoundly
-ˈsau̇n-(d)lē How to pronounce unsound (audio)
adverb
unsoundness
-ˈsau̇n(d)-nəs
noun

Medical Definition

unsound

adjective
un·​sound -ˈsau̇nd How to pronounce unsound (audio)
: not sound: as
a
: not healthy or whole
an unsound limb
an unsound horse
b
: not mentally normal : not wholly sane
of unsound mind
c
: not fit to be eaten
unsound food
unsoundness noun

Legal Definition

unsound

adjective
un·​sound ˌən-ˈsau̇nd How to pronounce unsound (audio)
: not sound: as
a
: not healthy or whole
b
: not mentally normal : not wholly sane
of unsound mind
c
: not firmly made, placed, or fixed
d
: not valid or true
an unsound argument
unsoundly adverb
unsoundness noun
Last Updated: - Updated example sentences
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