The Collaborative International Dictionary of English v.0.48:

Inauspicious \In`aus*pi"cious\, a.
   Not auspicious; ill-omened; unfortunate; unlucky;
   unfavorable. "Inauspicious stars." --Shak. "Inauspicious
   love." --Dryden. -- In`aus*pi"cious*ly, adv. --
   In`aus*pi"cious*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

inauspiciousness
    n 1: the quality of suggesting an unsuccessful result [syn:
         inauspiciousness, unpropitiousness] [ant:
         auspiciousness, propitiousness]