The Collaborative International Dictionary of English v.0.48:

AEsthetic \[AE]s*thet"ic\, AEsthetical \[AE]s*thet"ic*al\, a.
   Of or Pertaining to [ae]sthetics; versed in [ae]sthetics; as,
   [ae]sthetic studies, emotions, ideas, persons, etc.
   [1913 Webster] -- [AE]s*thet"ic*al*ly, adv.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

46 Moby Thesaurus words for "aesthetic":
   Attic, aesthetically appealing, art-conscious, artistic, arty,
   attractive, beauteous, beautiful, chaste, choice, classic,
   cultivated, discriminating, elegant, endowed with beauty,
   excellent, exquisite, eye-filling, fine, flowerlike, graceful,
   gracile, handsome, heavy, in good taste, lovely, of choice,
   of consummate art, of quality, ornamental, painterly, pleasing,
   pretty, pulchritudinous, pure, quiet, refined, restrained,
   sensitive, simple, subdued, tasteful, unaffected, understated,
   unobtrusive, well-chosen