i Register
In some senses, colourwash is marked as UK. Watch for register when choosing this word.
noun
A coloured distemper (paint)
Most of Axmouth's old houses, a mixture of colourwash and thatch, natural stone walls and tiled roofs, are grouped around the Church of St Michael with its handsome Norman doorway and medieval wall-paintings.
verb
To paint with a coloured distemper (paint).