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lactase

American  
[lak-teys, -teyz] / ˈlæk teɪs, -ˌteɪz /

noun

Biochemistry.
  1. an enzyme capable of hydrolyzing lactose into glucose and galactose.


lactase British  
/ ˈlækteɪs, -teɪz /

noun

  1. any of a group of enzymes that hydrolyse lactose to glucose and galactose

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

lactase Scientific  
/ lăktās′ /
  1. An enzyme that is found in the small intestine, liver, and kidneys of mammals and catalyzes the breakdown of lactose into galactose and glucose.


Etymology

Origin of lactase

First recorded in 1890–95; lact- + -ase

Vocabulary lists containing lactase

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Using the new reference panel, they analyzed how a genomic variant of the lactase gene is related to traits such as height, body mass index and low-density lipoprotein cholesterol, also known as "bad cholesterol."

From Science Daily • Nov. 7, 2023

But lactose is not fermentable, so it doesn’t get consumed by the yeast, which does not have the lactase enzyme and therefore is just as lactose-intolerant as any of your cheese-avoidant friends.

From Seattle Times • Feb. 8, 2023

Someone who is lactose intolerant, "wouldn't put corn syrup on cereal instead of milk," he pointed out, "they buy milk with lactase added," referring to the enzyme that digests lactose.

From Salon • Sep. 30, 2022

In a new report, scientists argue that the lactase mutation only became important to survival when Europeans began enduring epidemics and famines.

From New York Times • Jul. 28, 2022

It is possible to take lactase to break down the milk sugars for example; sometimes aids such as hydrochloric acid, pepsin, and pancreatin help.

From How and When to Be Your Own Doctor by Solomon, Steve