Glazing: Layering transparent watercolor over previously painted (dry) areas. This adds depth and richness of color.
Can be used to adjust intensity (darken or neutralize) the area being glazed.
Use a blue-toned glaze to help colors recede.
Use a red/yellow glaze to warm an area.
Multiple glazes create depth, can be used to create rich dark tones.
Take care when glazing to use a light hand, not to scrub the layers of colour beneath the glaze.