lactose

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noun lac·tose \ˈlak-ˌtōs, -ˌtōz\

Definition of lactose

  1. :  a disaccharide sugar C12H22O11 that is present in milk and yields glucose and galactose upon hydrolysis and yields especially lactic acid upon fermentation

Origin and Etymology of lactose

International Scientific Vocabulary


First Known Use: 1857



LACTOSE Defined for English Language Learners

lactose

play
noun lac·tose \ˈlak-ˌtōs, -ˌtōz\

Definition of lactose for English Language Learners

  • chemistry : a type of sugar that is present in milk


LACTOSE Defined for Kids

lactose

play
noun lac·tose \ˈlak-ˌtōs\

Definition of lactose for Students

  1. :  a sugar that is found in milk


Medical Dictionary

lactose

play
noun lac·tose \ˈlak-ˌtōs, -ˌtōz\

Medical Definition of lactose

  1. :  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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