Definition of lactase
: an enzyme that hydrolyzes beta-galactosides (such as lactose) and occurs especially in the intestines of young mammals and in yeasts
Recent Examples of lactase from the Web
The strongest signal of selection was a region on Chromosome 2 that contained the LCT gene producing lactase, the enzyme that breaks down the lactose in milk.
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Origin and Etymology of lactase
International Scientific Vocabulary
First Known Use: 1891See Words from the same year
Medical Definition of lactase
: an enzyme that hydrolyzes especially lactose to glucose and galactose and occurs especially in the intestines of young mammals and in yeasts
Seen and Heard
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