Main Entry:

un·sound

Pronunciation:

\-ˈsau̇nd\

Function:

adjective

Date:

14th century

: not sound: 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>

— un·sound·ly \-ˈsau̇n(d)-lē\ adverb