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Medical Term:


Pronunciation: ev′ō-lū′shŭn


  1. A continuing process of change from one state, condition, or form to another.
  2. A progressive distancing between the genotype and the phenotype in a line of descent.
  3. The liberation of a gas or heat in the course of a chemical or enzymatic reaction.

[L. e-volvo, pp. -volutus, to roll out]