Biochemistry. a disaccharide, C12H22O11, present in milk, that upon hydrolysis yields glucose and galactose.
a white, crystalline, sweet, water-soluble commercial form of this compound, obtained from whey and used in infant feedings, in confections and other foods, in bacteriological media, and in pharmacology as a diluent and excipient.
Origin of lactose
First recorded in 1855–60; lact-
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Related Words for lactosesugar
Examples from the Web for lactose
Historical Examples of lactose
British Dictionary definitions for lactose
a white crystalline disaccharide occurring in milk and used in the manufacture of pharmaceuticals and baby foods. Formula: C 12 H 22 O 11Also called: milk sugar
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for lactose
sugar from milk, 1858, from French, coined by French chemist Marcelin-Pierre-Eugène Berthelot (1827-1907) from Latin lac (genitive lactis) "milk" (see lactation) + chemical suffix -ose (2).
Online Etymology Dictionary, © 2010 Douglas Harper
A disaccharide in milk that hydrolyzes to yield glucose and galactose.milk sugar
A white crystalline substance obtained from whey and used in infant foods and in pharmaceuticals as a diluent and excipient.milk sugar
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
A white crystalline disaccharide consisting of a glucose and a galactose molecule, found in milk and used in the manufacture of various other foods. Chemical formula: C12H22O11.
The inability to digest lactose properly is called lactose intolerance. It is caused by a deficiency of the enzyme lactase and marked by abdominal cramping and other symptoms after ingesting lactose.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.