unsound

adjective

un·​sound ˌən-ˈsau̇nd How to pronounce unsound (audio)
: 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 adverb

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.
The money would go to Metro, the physically unsafe and fiscally unsound public transit system that saw its ridership peak in the 1980s. Susan Shelley, Oc Register, 12 Apr. 2025 Democrats dismiss the effort as purely political and legally unsound since the series of court rulings GOP lawmakers are fighting come down to a a disagreement about the law, not high crimes or corruption on the part of judges. Deirdre Walsh, NPR, 25 Mar. 2025 One wall in 18-20 Trinity St. — originally built for an insurance company — is structurally unsound. Kenneth R. Gosselin, Hartford Courant, 25 Mar. 2025 Constructed in the 1950s with additions from the 1970s, the building was determined to have a structurally unsound central pillar — which the authorities believe to be the cause of the collapse, the Associated Press reported. Rachel Raposas, People.com, 11 Mar. 2025 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

Browse Nearby Words

Cite this Entry

“Unsound.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsound. Accessed 21 Apr. 2025.

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 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

More from Merriam-Webster on unsound

Last Updated: - Updated example sentences
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