: a disaccharide sugar C12H22O11 that is present in milk and yields glucose and galactose upon hydrolysis and yields especially lactic acid upon fermentation
Examples of lactose in a Sentence
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With less lactose than regular, unstrained yogurts, both Greek yogurt and skyr might be suitable for some people with lactose intolerance, but not necessarily for all.
—
Lauren O'Connor, Ms, Health, 3 Feb. 2025
As a result, the body can only tolerate a certain quantity of lactose, which differs from one individual to another.
—Marie Bladt, Vogue, 24 Dec. 2024
People sensitive to lactose should choose ghee over butter, as ghee is nearly lactose-free.
—Jillian Kubala, Health, 15 Jan. 2025
Some individuals—many more than have allergies to milk—are intolerant to it, meaning their bodies struggle to digest dairy products, usually due to milk sugar called lactose.
—Yaakov Katz, Newsweek, 17 Jan. 2025
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Lauren O'Connor, Ms, Health, 3 Feb. 2025
As a result, the body can only tolerate a certain quantity of lactose, which differs from one individual to another.
—Marie Bladt, Vogue, 24 Dec. 2024
People sensitive to lactose should choose ghee over butter, as ghee is nearly lactose-free.
—Jillian Kubala, Health, 15 Jan. 2025
Some individuals—many more than have allergies to milk—are intolerant to it, meaning their bodies struggle to digest dairy products, usually due to milk sugar called lactose.
—Yaakov Katz, Newsweek, 17 Jan. 2025
See all Example Sentences for lactose
Dictionary Entries Near lactose
Cite this Entry
“Lactose.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lactose. Accessed 19 Feb. 2025.
Copy CitationKids Definition
lactose
noun
lac·tose
ˈlak-ˌtōs 
: a sugar present in milk that breaks down to give glucose and galactose and on fermentation gives especially lactic acid
called also milk sugar
Medical Definition
lactose
noun
lac·tose
ˈlak-ˌtōs, -ˌtōz
: a disaccharide sugar C12H22O11 that is present in milk, yields glucose and galactose upon hydrolysis, yields especially lactic acid upon fermentation, and is used chiefly in foods, medicines, and culture media (as for the manufacture of penicillin)
called also milk sugar
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