Dialysis \Di*al"y*sis\, n.; pl. Dialyses. [L., separation, fr. Gr. ?, fr. ? to part asunder, dissolve; dia` through + ? to loose.]

1. (Gram.) Di[ae]resis. See Di[ae]resis, 1.

2. (Rhet.) Same as Asyndeton.

3. (Med.)
   (a) Debility.
   (b) A solution of continuity; division; separation of parts.

4. (Chem.) The separation of different substances in solution, as crystalloids and colloids, by means of their unequal diffusion, especially through natural or artificial membranes.

Source: Webster's Revised Unabridged Dictionary (1913)