Source : Webster's Revised Unabridged Dictionary (1913)

Openwork \O"pen*work`\, n.
   1. Anything so constructed or manufactured (in needlework,
      carpentry, metal work, etc.) as to show openings through
      its substance; work that is perforated or pierced.

   2. (Mining) A quarry; an open cut. --Raymond.

Source : WordNet®

openwork
     n : ornamental work (such a embroidery or latticework) having a
         pattern of openings