lactose

[lak-tohs]

noun

1. Biochemistry.,  a disaccharide, C 12 H 22 O 11 , present in milk, that upon hydrolysis yields glucose and galactose.

2. 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.

lactose

/ ˈlæktəʊs, -təʊz /

noun

1. Also called: milk sugar. a white crystalline disaccharide occurring in milk and used in the manufacture of pharmaceuticals and baby foods. Formula: C 12 H 22 O 11

lactose

1. 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: C ₁₂ H ₂₂ O ₁₁ .

2. 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.

Word History and Origins

Origin of lactose¹

First recorded in 1855–60; lact- + -ose ²

Example Sentences

Plant-based milks, despite existing for millennia, rose to global popularity amid the 21st century due to growing concerns of lactose intolerance and the environmental impacts of dairy.

From Salon

They argue a lack of lactose, no cholesterol and lower amounts of saturated fats in lab-made cheese can boost its health benefits - and that any cheese is processed.

From BBC

Their innuendo-laden pop anthem Milkshake Man had received a warm reception ahead of the contest but, on the night, viewers proved to be lactose intolerant.

From BBC

At one time or another, you've probably come across someone who is lactose intolerant and might experience some unpleasant gut symptoms if they have dairy.

From Salon

First, they analyzed genetic data from over 542,000 women and focused on variants — tiny changes in DNA — associated with lactase persistence, the ability to digest lactose in adulthood.

From Salon

Related Words

• cellulose 
• glucose 
• starch 
• sugar