[ uhn-sound ]
/ ʌnˈsaʊnd /

adjective, un·sound·er, un·sound·est.

not sound; unhealthy, diseased, or disordered, as the body or mind.
decayed or impaired, as timber or foods; defective.
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.


Can You Ace This Quiz About “Compliment” vs. “Complement”?
Take this quiz to see if you really know the difference between “compliment” and “complement"!
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“Compliment” and “complement” had a shared meaning a long time ago, but today they are no longer interchangeable.

Origin of unsound

Middle English word dating back to 1275–1325; see origin at un-1, sound2


un·sound·ly, adverbun·sound·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for unsound

British Dictionary definitions for unsound

/ (ʌnˈsaʊnd) /


diseased, weak, or unstableof unsound mind
unreliable or fallaciousunsound advice
lacking solidity, strength, or firmnessunsound foundations
of doubtful financial or commercial viabilityan unsound enterprise
(of fruit, timber, etc) not in an edible or usable condition

Derived forms of unsound

unsoundly, adverbunsoundness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012