unsound
Americanadjective
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not sound; unhealthy, diseased, or disordered, as the body or mind.
-
decayed or impaired, as timber or foods; defective.
- Synonyms:
- unwholesome, rotten
-
not solid or firm, as foundations.
-
not well-founded or valid; fallacious.
an unsound argument.
-
easily broken; light.
unsound slumber.
-
not financially strong; unreliable.
an unsound corporation.
adjective
-
diseased, weak, or unstable
of unsound mind
-
unreliable or fallacious
unsound advice
-
lacking solidity, strength, or firmness
unsound foundations
-
of doubtful financial or commercial viability
an unsound enterprise
-
(of fruit, timber, etc) not in an edible or usable condition
Other Word Forms
Derived Forms
Etymology
Origin of unsound
Middle English word dating back to 1275–1325; see origin at un- 1, sound 2
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Germany is uniquely neurotic about debt and about unsound money.
From BBC • Mar. 27, 2026
She’s right about that, but this manual included some unsound science.
From The Wall Street Journal • Feb. 8, 2026
That assessment was technically accurate but fundamentally unsound.
From Slate • Mar. 28, 2025
The surface pleasures of “Y2K” are outlandishly fun, but plot-wise, the film is structurally unsound.
From Los Angeles Times • Dec. 6, 2024
Although swidden does permit the forest to regrow, it is wildly inefficient and environmentally unsound.
From "1491" by Charles C. Mann
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.