: 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
Recent Examples on the Web
Lassi may help with digestion, symptoms of irritable bowel syndrome (IBS), and may be easier to tolerate for people with lactose intolerance.1516
Some research also links it to improved heart health, blood sugar management, and immune system function.1716
8.
—
Jonathan Purtell, Verywell Health, 23 May 2025
Certain foods, swallowed air, or sensitivity to specific ingredients, such as lactose in dairy products, can also cause increased stomach sounds unrelated to hunger.4
Is there a way to make stomach growling less noticeable?
—Lindsay Curtis, Health, 21 May 2025
The conclave that elected the late Pope Francis used a combination of potassium chlorate, lactose, and chloroform resin to create white smoke, which appears to have solved the visibility problem.
—Laura Baisas, Popular Science, 1 May 2025
The undigested lactose causes symptoms.1 Newborns and babies can usually digest lactose, but this ability decreases over time.
—Amber J. Tresca, Verywell Health, 19 May 2025
See All Example Sentences for lactose
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Jonathan Purtell, Verywell Health, 23 May 2025
Certain foods, swallowed air, or sensitivity to specific ingredients, such as lactose in dairy products, can also cause increased stomach sounds unrelated to hunger.4
Is there a way to make stomach growling less noticeable?
—Lindsay Curtis, Health, 21 May 2025
The conclave that elected the late Pope Francis used a combination of potassium chlorate, lactose, and chloroform resin to create white smoke, which appears to have solved the visibility problem.
—Laura Baisas, Popular Science, 1 May 2025
The undigested lactose causes symptoms.1 Newborns and babies can usually digest lactose, but this ability decreases over time.
—Amber J. Tresca, Verywell Health, 19 May 2025
See All Example Sentences for lactose
Cite this Entry
“Lactose.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lactose. Accessed 5 Jun. 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
Love words? Need even more definitions?
Merriam-Webster unabridged
Share