The point, at a given temperature and pressure, at which all the solute that can be dissolved by a solvent into a particular solution has been dissolved. In some cases (usually the result of changes in temperature and/or pressure) a solution can become supersaturated, in which case more solute than can typically be dissolved does go into solution. However, in the case of supersaturated solutions, the addition of a small solid particle or the jostling of the container can cause the extraneous solute to precipitate out.
In color terminology, saturation refers to a color attribute and one of the three axes on various color models (such as the CIE Color Space) that describes a particular color's intensity, lightness or darkness, or the degree to which a color departs from a gray of comparable lightness. In other words, the extent that a particular color comprises a selected hue rather than white.