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lactase Line breaks: lac|tase
Pronunciation: /ˈlakteɪz/

Definition of lactase in English:


[mass noun] Biochemistry
An enzyme which catalyses the hydrolysis of lactose to glucose and galactose.
Example sentences
  • The enzyme lactase breaks down the lactose to galactose and glucose.
  • Many people take extra doses of naturally produced enzymes, such as lactase, pepsin and trypsin, in supplement form.
  • Lactose, the sugar present in milk, is split in the small intestine by the enzyme lactase into its constituent glucose and galactose molecules, allowing absorption of the glucose.


Late 19th century: from lactose + -ase.

Words that rhyme with lactase

chrysoprase • equites

Definition of lactase in:

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