Source : Webster's Revised Unabridged Dictionary (1913)

Unholy \Un*ho"ly\, a.
   Not holy; unhallowed; not consecrated; hence, profane;
   wicked; impious. -- {Un*ho"li*ly}, adv. -- {Un*ho"li*ness},
   n.

Source : WordNet®

unholiness
     n : the quality of being unholy [ant: {holiness}]