1. 
[syn: amazing, awe-inspiring, awesome, awful, awing]
The Collaborative International Dictionary of English v.0.48:
Awesome \Awe"some\, a.
   1. Causing awe; appalling; awful; as, an awesome sight.
      --Wright.
      [1913 Webster]
   2. Expressive of awe or terror.
      [1913 Webster]
            An awesome glance up at the auld castle. --Sir W.
                                                  Scott.
      [1913 Webster]
WordNet (r) 3.0 (2006):
awesome
    adj 1: inspiring awe or admiration or wonder; "New York is an
           amazing city"; "the Grand Canyon is an awe-inspiring
           sight"; "the awesome complexity of the universe"; "this
           sea, whose gently awful stirrings seem to speak of some
           hidden soul beneath"- Melville; "Westminster Hall's awing
           majesty, so vast, so high, so silent" [syn: amazing,
           awe-inspiring, awesome, awful, awing]
Moby Thesaurus II by Grady Ward, 1.0:
143 Moby Thesaurus words for "awesome":
   Gargantuan, affecting, aggrandized, alarming, amazing,
   amplitudinous, apotheosized, appalling, astonishing, astounding,
   astronomical, august, awe-inspiring, awful, awing, beatified, big,
   bizarre, boundless, breathtaking, bulky, canonized, colossal,
   cosmic, daunting, deified, dire, direful, divine, dread, dreaded,
   dreadful, eerie, elevated, eminent, ennobled, enormous, enshrined,
   enthroned, estimable, exalted, excellent, extensive, fearful,
   fearsome, fell, formidable, frightening, galactic, ghastly,
   ghoulish, gigantic, glorified, grand, great, grim, grisly,
   gruesome, heavenly, held in awe, hideous, high, high and mighty,
   holy, honorable, horrendous, horrible, horrid, horrific,
   horrifying, huge, immeasurable, immense, immortal, immortalized,
   imposing, incredible, ineffable, inenarrable, inexpressible,
   infinite, inviolable, inviolate, king-size, large, lofty, macabre,
   magnified, mammoth, massive, massy, mighty, monster, monstrous,
   monumental, morbid, mountainous, moving, mysterious, numinous,
   outsize, overgrown, overwhelming, prodigious, redoubtable,
   religious, reverend, sacred, sacrosanct, sainted, sanctified,
   schrecklich, shocking, shrined, sizable, spacious, spiritual,
   stirring, stunning, stupefying, stupendous, sublime, supereminent,
   terrible, terrific, terrifying, throned, time-honored, titanic,
   tremendous, unbelievable, uncanny, unspeakable, untouchable,
   unutterable, vast, venerable, voluminous, weighty, weird,
   wonderful, wondrous, worshipful