ガッシュ グヮッシュ
Similar in both theory and practice to [[watercolor (medium)|watercolor]]s, gouache has the distinction of laying opaque pigment on a substrate and using the water as a binder rather than to staining the substrate directly.  Long favoured by illustrators for its ability to cover large areas, many old [[movie poster]]s are painted with this medium.  Notably, it can also be applied via pen or airbrush.
gouache (medium)