galactose

American  

[guh-lak-tohs] / gəˈlæk toʊs /

noun

Chemistry.

1. a white, crystalline, water-soluble hexose sugar, C 6 H 12 O 6 , obtained in its dextrorotatory form from milk sugar by hydrolysis and in its levorotatory form from mucilages.

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galactose British  

/ -əʊs, ɡəˈlæktəʊz /

noun

1. a white water-soluble monosaccharide found in lactose. Formula: C 6 H 12 O 6

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galactose Scientific  

/ gə-lăk′tōs′ /

1. A monosaccharide commonly occurring in lactose and in certain pectins, gums, and mucilages. Chemical formula: C ₆ H ₁₂ O ₆ .

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Etymology

Origin of galactose

First recorded in 1865–70; galact- + -ose ²

Example Sentences

This enzyme enables the bacteria to generate galactose directly from glucose.

From Science Daily • Jan. 13, 2026

Two major carbohydrate components were studied: fucose and galactose.

From Science Daily • Jan. 9, 2026

Following her illness, Mills was diagnosed with galactosaemia, a rare genetic disorder affecting up to one in 45,000 babies which prevents her body from turning galactose into glucose.

From BBC • Jan. 9, 2024

All mammals, including humans, make milk with carbohydrates in the same unique form: lactose, a sugar that is a fusion of two other sugars called galactose and glucose.

From Salon • Sep. 30, 2022

H2SO4 at 130-135°, soluble carbohydrates were obtained, amongst which mannose was identified, and galactose shown to be present in some quantity.

From Researches on Cellulose 1895-1900 by Cross, C. F.

Related Words

• cellulose
• glucose
• lactose
• starch
• sugar