A glaze is a thin, transparent layer of paint laid over a dried under-layer, modifying the colour beneath without obscuring it.
A glaze reads as smooth and even rather than broken; it shifts the hue, warmth, or depth of what is below by tinting it through a translucent film. Traditional oil glazing builds form through many such layers, each adjusting tone and temperature subtly, producing the inner luminosity associated with old-master flesh, fabric, and shadow. Description distinguishes a glaze from a scumble (broken, semi-opaque), from a wash (fluid, often watery, on absorbent ground), and from a wet-into-wet blend (mixed on the surface itself). The presence of glazing is read by depth: glazed colour seems lit from within because the eye sees through the upper layer to the layers beneath.