emulsion

(ĕ-mŭl′shŏn)
[L. emulsio, a milking out]

1. A mixture of two liquids not mutually soluble. If they are thoroughly shaken, one divides into globules in what is called the discontinuous or dispersed phase; the other is then the continuous phase. Milk is an emulsion in which butterfat is the discontinuous phase.
2. In radiology, the part of the radiographic film sensitive to radiation and containing the image after development.

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