overglaze

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An outer coat of glaze on a piece of pottery.
• noun A painted or printed decoration applied over a glaze.
• transitive verb To apply an overglaze to.
• adjective Applied or designed for applying over a ceramic glaze.

from The Century Dictionary.

• To glaze over; cover with superficial brilliancy; hide (an inferior material) with something more showy.
• noun In ceramics, a second glaze applied to a piece of porcelain of which the first glaze is deeply colored or crackled, or covered with paintings in enamel.
• In ceramics, used for painting upon the glaze: said of a vitrifiable pigment: as, an overglaze color.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Applied over the glaze; -- said of enamel paintings, which sometimes are seen to project from the surface of the ware.
• adjective Suitable for applying upon the glaze; -- said of vitrifiable colors used in ceramic decoration.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The outer layer or coat of glaze on a piece of pottery
• noun A decoration, usually enamel, applied over a glaze.