The Collaborative International Dictionary of English v.0.48:

Auspicious \Aus*pi"cious\, a. [See Auspice.]
   1. Having omens or tokens of a favorable issue; giving
      promise of success, prosperity, or happiness; predicting
      good; as, an auspicious beginning.
      [1913 Webster]

            Auspicious union of order and freedom. --Macaulay.
      [1913 Webster]

   2. Prosperous; fortunate; as, auspicious years. "Auspicious
      chief." --Dryden.
      [1913 Webster]

   3. Favoring; favorable; propitious; -- applied to persons or
      things. "Thy auspicious mistress." --Shak. "Auspicious
      gales." --Pope.
      [1913 Webster]

   Syn: See Propitious.
        [1913 Webster] -- Aus*pi"cious*ly, adv. --
        Aus*pi"cious*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

auspicious
    adj 1: auguring favorable circumstances and good luck; "an
           auspicious beginning for the campaign" [ant:
           inauspicious, unfortunate]

Moby Thesaurus II by Grady Ward, 1.0:

87 Moby Thesaurus words for "auspicious":
   advantageous, appropriate, befitting, beneficial, benevolent,
   benign, benignant, blessed, blessed with luck, bon, bonny, braw,
   bright, bright with promise, bueno, capital, cheering, cogent,
   commendable, convenient, dexter, elegant, encouraging, estimable,
   excellent, expedient, fair, famous, favorable, favored, favoring,
   felicitous, fine, fit, fitting, fortunate, full of promise, golden,
   good, goodly, grand, halcyon, happy, healthy, helpful, hopeful,
   in luck, inspiring, inspiriting, kind, laudable, looking up, lucky,
   meet, nice, noble, of good omen, of happy portent, of promise,
   opportune, pleasant, pregnant of good, profitable, promising,
   propitious, prosperous, providential, reassuring, regal, ripe,
   roseate, rosy, royal, seasonable, skillful, sortable, sound,
   splendid, suitable, supportive, timely, useful, valid, very good,
   virtuous, well-timed, white