Simple Definition of unsound

from our Learner's Dictionary

unsound

adjective

1
: not based on truth or logic : not showing good judgment
unsound [=faulty] arguments
unsound business practices
2
: poorly built or in bad condition
an unsound [=unsafe] building
The roof is structurally unsound.

Cite this Entry

“Unsound.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/unsound. Accessed 21 Apr. 2026.

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