Galactose n. : A white, crystalline sugar, C6H12O6, isomeric with dextrose, obtained by the decomposition of milk sugar, and also from certain gums. When oxidized it forms mucic acid. Called also lactose (though it is not lactose proper).

Example:
What to do with terminal Galactose in my body?

Taxonomy
galactose metabolism, lactose, ovarian cancer, free encyclopedia, PMID, D-galactose, risk, glc, grams, free diet, the Risk, mice, correlation, OH groups, deficiencies, Galactose-1-phosphate uridyl transferase, Tigas, Haymond.

Defination from the web:
galactose is catalyzed by the enzyme lactase, a β-galactosidase. In the human body, glucose is changed into galactose via hexoneogenesis in order to enable the mammary glands to secrete lactose. ...