Gouache, body colour, opaque watercolour, or guache, is one type of watermedia, paint consisting of pigment, water, a binding agent (usually dextrin or gum arabic), and sometimes additional inert material. Gouache is designed to be used with opaque methods of painting. The term, derived from the Italian guazzo, also refers to paintings using this opaque method.
Gouache has a considerable history going back over 600 years. It is similar to watercolour because it can be rewet and the paint can become infused with its paper support. It can also form a superficial layer like acrylic or oil paint. Also like watercolour, gouache dries to a matte finish. It is similar to acrylic or oil paints in that it is normally used in an opaque painting style. Many manufacturers of watercolour paints also produce gouache and the two can easily be used together.