Source : Webster's Revised Unabridged Dictionary (1913)

Fretwork \Fret"work\, n. [6th fret + work.]
   Work adorned with frets; ornamental openwork or work in
   relief, esp. when elaborate and minute in its parts. Hence,
   any minute play of light and shade, dark and light, or the
   like.

         Banqueting on the turf in the fretwork of shade and
         sunshine.                                --Macaulay.

Source : WordNet®

fretwork
     n : framework consisting of an ornamental design made of strips
         of wood or metal [syn: {lattice}, {latticework}]