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Medical Term:


Pronunciation: ās


A termination denoting an enzyme, suffixed to the name of the substance (substrate) on which the enzyme acts; phosphatase, lipase, proteinase. May also indicate the reaction catalyzed, decarboxylase, oxidase. Enzymes named before this naming convention was established generally have an -in ending; pepsin, ptyalin, trypsin.

[Fr. (diast)ase, an amylase that converts starch to maltose, fr. G. diastasis, separation, fr. dia-, through, apart, + stasis, a standing]

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