Water-mixable oil paint

Water-mixable oil paint (also called "water soluble" or "water miscible") is a modern type of oil paint.
It is designed to be thinned and cleaned up with water. This avoids using turpentine, whose fumes may be harmful if inhaled, and is a fires risk. 
Water miscible oil paint can be mixed and used with the same techniques as traditional oil-based paint. When it is still wet, it can be removed from brushes, palettes, and rags with ordinary soap and water. Its water solubility comes from the use of an oil medium in which one end of the molecule has been altered to bind loosely to water molecules, as in a solution.
Another advantage of this type of oil paint is that it dries faster than traditional oils (but slower than acrylics). Also, painters can control the speed of drying with supplementary products from artistic paint suppliers.