unsoundness

from WordNet (r) 3.0 (2006)

unsoundness
    n 1: a condition of damage or decay [ant: {soundness}]
    2: a misconception that is fallacious and not true or valid;
       "the unsoundness of his conclusion was obvious"
    3: not mentally or physically healthy; "no one can be a poet
       without a certain unsoundness of mind" [ant: {firmness},
       {soundness}, {wisdom}, {wiseness}]

from The Collaborative International Dictionary of English v.0.48

Unsound \Un*sound"\, a.
   Not sound; not whole; not solid; defective; infirm; diseased.
   [1913 Webster] -- {Un*sound"ly}, adv. -- {Un*sound"ness}, n.
   [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

UNSOUNDNESS. Vide Crib-biting; Roaring; Soundness.

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