Glazing: Glazing is a historic painting technique whereby one applies a thin layer of darker color over a brighter, dried surface, thereby superimposing one transparent color over another to achieve a planned result. GottliebStudios.com/Classical_Glossary
The effect of a glaze is that the resulting color is more transparent and optically more orange.
The paint prepared for a glaze can be diluted by a medium to achieve greater fluidity and saturation, or it can be dry scrubbed on so as to be less watery.
Glazing creates a unique luminosity that is not obtainable through direct painting. The glaze heightens and increases the depth of color and brightness of the underpainting rather than obscuring it. The concepts inherently understood in glazing can be applied indirectly to direct painting.