The Collaborative International Dictionary of English v.0.48:

Cloisonn'e \Cloi`son*n['e]\, a. [F., partitioned, fr. cloison a
   partition.]
   Inlaid between partitions: -- said of enamel when the lines
   which divide the different patches of fields are composed of
   a kind of metal wire secured to the ground; as distinguished
   from champlev['e] enamel, in which the ground is engraved
   or scooped out to receive the enamel. --S. Wells Williams.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cloisonne
    adj 1: (for metals) having areas separated by metal and filled
           with colored enamel and fired [syn: champleve,
           cloisonne]
    n 1: enamelware in which colored areas are separated by thin
         metal strips