The Collaborative International Dictionary of English v.0.48:

Beauteous \Beau"te*ous\ (b[=u]"t[-e]*[u^]s), a.
   Full of beauty; beautiful; very handsome. [Mostly poetic] --
   Beau"te*ous*ly, adv. -- Beau"te*ous*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

beauteous
    adj 1: (poetic )beautiful, especially to the sight

Moby Thesaurus II by Grady Ward, 1.0:

21 Moby Thesaurus words for "beauteous":
   aesthetic, aesthetically appealing, attractive, beautiful, bonny,
   comely, elegant, endowed with beauty, exquisite, eye-filling, fair,
   fine, flowerlike, good-looking, graceful, gracile, handsome, heavy,
   lovely, pretty, pulchritudinous