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Medical Term:


Pronunciation: di-al'i-sis


  1. A form of filtration to separate crystalloid from colloid substances (or smaller molecules from larger ones) in a solution by interposing a semipermeable membrane between the solution and dialyzing fluid; the crystalloid (smaller) substances pass through the membrane into the dialyzing fluid on the other side, the colloids do not.
  2. The separation of substances across a semipermeable membrane on the basis of particle size or concentration gradients.
  3. A method of artificial kidney function.

[G. a separation, fr. dialyo, to separate]

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