ENGLISH
REFERENCE

lactose

n. uncountable
B2 Upper Intermediate US //ˈɫæktoʊs// UK //lˈæktəʊz// lac·tose

n. a type of sugar found in milk and dairy products. Many people find it hard to digest, which can cause stomach problems.

n. a disaccharide sugar present in milk, consisting of glucose and galactose units. It is broken down in the digestive system by the enzyme lactase.


SIMPLE

This milk is special because it does not contain any lactose.

CONTEXTUAL

Many adults develop a sensitivity to lactose and choose plant-based alternatives like almond or soy milk.

COMPLEX

The inability to produce sufficient lactase leads to the fermentation of undigested lactose in the colon, resulting in the gastrointestinal symptoms associated with intolerance.

Origin

Borrowed from French lactose, from Latin lac (“milk”) + -ose (derivation of glucose). Coined by French chemist Marcelin Berthelot.

Usage

Uncountable in its chemical and dietary sense; often appears in the compound 'lactose intolerance'.

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