underglaze color
Technical term in ceramics for pigment applied to bisque-fired ware before glazing and firing.
In pottery, you paint a design with underglaze color and then apply the glaze.
Compound of 下絵 (preliminary sketch, underdrawing) + の (possessive particle) + 具 (tool, ingredient, pigment). The term refers to pigment used for the design beneath the glaze.