n. A draining out.n. A mixture of liquids insoluble in one another, where one is suspended in the other in the form of minute globules, as the fat (butter) in milk: as, an emulsion of cod-liver oil.n. A mixture in which solid particles are suspended in a liquid in which they are insoluble: as, a camphor emulsion.n. In photography, a name given to various emulsified mixtures used in making dry plates, etc. See photography.n. Unwashed, a collodion containing finely divided silver bromide held in suspension.