The Collaborative International Dictionary of English v.0.48:

Arabesque \Ar`a*besque"\, a.
   1. Arabian. [Obs.]
      [1913 Webster]

   2. Relating to, or exhibiting, the style of ornament called
      arabesque; as, arabesque frescoes.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Arabesque \Ar`a*besque"\, n. [F. arabesque, fr. It. arabesco,
   fr. Arabo Arab.]
   A style of ornamentation either painted, inlaid, or carved in
   low relief. It consists of a pattern in which plants, fruits,
   foliage, etc., as well as figures of men and animals, real or
   imaginary, are fantastically interlaced or put together.
   [1913 Webster]

   Note: It was employed in Roman imperial ornamentation, and
         appeared, without the animal figures, in Moorish and
         Arabic decorative art. (See Moresque.) The arabesques
         of the Renaissance were founded on Greco-Roman work.
         [1913 Webster]

WordNet (r) 3.0 (2006):

arabesque
    n 1: position in which the dancer has one leg raised behind and
         arms outstretched in a conventional pose
    2: an ornament that interlaces simulated foliage in an intricate
       design

Moby Thesaurus II by Grady Ward, 1.0:

99 Moby Thesaurus words for "arabesque":
   acciaccatura, appoggiatura, baroque, baroqueness, basketry,
   basketwork, cadence, cadenza, cancellation, chinoiserie,
   coloratura, cross-hatching, crossing-out, division, elaborateness,
   elegance, embellishment, fanciness, filigree, fineness, fioritura,
   flamboyance, flight, floridity, floridness, flourish, floweriness,
   fret, fretwork, grace, grace note, grate, grating, grid, gridiron,
   grille, grillwork, hachure, hatching, incidental, incidental note,
   interlacement, intertexture, intertwinement, lace, lacery,
   lacework, lacing, lattice, latticework, long mordent, luxuriance,
   luxuriousness, mesh, meshes, meshwork, mordent, moresque, net,
   netting, network, ornament, ostentation, overelaborateness,
   overelegance, overornamentation, passage, plexure, plexus,
   pralltriller, raddle, reticle, reticulation, reticule, reticulum,
   richness, riddle, rococo, roulade, run, screen, screening, sieve,
   single mordent, texture, tissue, tracery, trellis, trelliswork,
   turn, wattle, weave, weaving, web, webbing, webwork, weft, wicker,
   wickerwork