Miscibility

Miscibility /mɪsɨˈbɪlɨti/ is the property of liquids to mix in all proportions, forming a homogeneous solution. In principle, the term applies also to other phases (solids and gases), but the main focus is usually on the solubility of one liquid in another. Water and ethanol, for example, are miscible because they mix in all proportions.

By contrast, substances are said to be immiscible if in some proportion, they do not form a solution. For example, diethyl ether is fairly soluble in water, but these two solvents are not miscible because they are not soluble in all proportions.