lactase

noun
lac·​tase | \ˈlak-ˌtās, -ˌtāz\

Definition of lactase 

: an enzyme that hydrolyzes beta-galactosides (such as lactose) and occurs especially in the intestines of young mammals and in yeasts

Examples of lactase in a Sentence

Recent Examples on the Web

Drinking milk after your lactase gene is turned off is no fun. Bob Gathany, AL.com, "Up in the air at the Huntsville Community Kite Festival," 4 Mar. 2018 Famous enzymes include lactase, which breaks down milk sugars in those who are lactose tolerant. Ian Haydon, Scientific American, "Enzymes versus Nerve Agents: Designing Antidotes for Chemical Weapons," 11 Apr. 2017 However, once the infants are weaned, the lactase-producing gene is turned off. Bob Gathany, AL.com, "Up in the air at the Huntsville Community Kite Festival," 4 Mar. 2018 During fermentation, bacteria break down milk sugars including lactase, turning them into acids and easing digestion for those with lactose intolerance. Brian Handwerk, Smithsonian, "How Cheese, Wheat and Alcohol Shaped Human Evolution," 7 May 2016 To digest lactose requires an enzyme called lactase, which infants of all mammals produce. Bob Gathany, AL.com, "Up in the air at the Huntsville Community Kite Festival," 4 Mar. 2018 This is one cause of lactase deficiency and lactose intolerance. Korin Miller, SELF, "Gastroenterologists Share 7 Things to Do When You Have Painful Gas," 14 Dec. 2017 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. Aatish Bhatia, WIRED, "Milk, meat and blood: how diet drives natural selection in the Maasai," 30 Sep. 2012

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lactase.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of lactase

1891, in the meaning defined above

History and Etymology for lactase

International Scientific Vocabulary

Keep scrolling for more

Learn More about lactase

Statistics for lactase

Look-up Popularity

Time Traveler for lactase

The first known use of lactase was in 1891

See more words from the same year

Keep scrolling for more

More Definitions for lactase

lactase

noun
lac·​tase | \ˈlak-ˌtās, -ˌtāz \

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

More from Merriam-Webster on lactase

Rhyming Dictionary: Words that rhyme with lactase

Britannica.com: Encyclopedia article about lactase

Comments on lactase

What made you want to look up lactase? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

a soft lustrous wool fabric with mohair

Get Word of the Day daily email!

Test Your Vocabulary

Late Autumn 2018 Words of the Day Quiz

  • frosted-autumn-leaves
  • Which is a synonym of yahoo?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!