Emulsion (?), n. [From L. emulgere, emulsum: cf. F. émulsion. See Emulge.] Any liquid preparation of a color and consistency resembling milk; as: (a) In pharmacy, an extract of seeds, or a mixture of oil and water united by a mucilaginous substance. (b) In photography, a liquid preparation of collodion holding salt of silver, used in the photographic process.
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