colour wash 
noun [mass noun]
Coloured distemper.Using a combination of line drawing and colour wash, Larkin observes the movements of a variety of urban characters....
- Standing at arm's length from the wall, brush the light colour wash over the walls in a haphazard way.
- There are two techniques for color wash application: sponge or brush.
verb (colour-wash) [with object]
Paint (something) with coloured distemper: the wall had been recently pointed and colour-washed...
- Half-rendered, half brick walls can be made charming by colour-washing them in smart paint and planting climbers to tone.
- The exhibits are for the most part Matcham's own colour-washed drawings, high-quality full-size reproductions of those held in London's Theatre Museum.
- As a bonus, subtle color-washed drawings by Bob Freeman are used in four stories, borrowed from the original Classic Cars series.