Term: Mud

Mud or muddy is a term used to describe what happens to paint when too many pigments are combined. The result is a color that is no longer bright and pure but rather dull and desaturated. Mud is typically a gray color. That being said, the term only applies to grays that look drab or bland in a given composition. The muddy effects come more from poorly designed values and color temperatures than color mixing. For example, a gray might be considered muddy if it is surrounded by other similar grays or if it is used in unattractive ways, while the same gray may work perfectly well in an appropriate context. As Richard Schmid states:

"There are no 'beautiful' or 'ugly' colors. Muddy colors are simply mixtures that are the inappropriate relative temperature for the area in which they are placed."

Muddy may also be used to describe the unintended desaturation of color that occurs when mixing with a dirty brush or overworking wet-on-wet paint. Dead or dirty are other terms that are occasionally used to describe over-mixed colors.