ga·​lac·​to·​si·​dase gə-ˌlak-ˈtō-sə-ˌdās How to pronounce galactosidase (audio)
: an enzyme (such as lactase) that hydrolyzes a galactoside

Examples of galactosidase in a Sentence

Recent Examples on the Web Here, too, beta-galactosidase and other compounds linked to senescence appeared in mouse embryos. Amber Dance, Smithsonian Magazine, 29 Dec. 2022 Scientists have found a handy way to identify many senescent cells by using stains that turn blue in the presence of a lysosome enzyme, called beta-galactosidase, that’s often overactive in these cells. Amber Dance, Smithsonian Magazine, 29 Dec. 2022 Or test your tolerance for small portions of less-gassy legumes like lentils and chickpeas with the aid of a bean-fiber-busting enzyme supplement called alpha galactosidase. SELF, 30 Nov. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'galactosidase.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


galactoside + -ase (perhaps after French galactosidase)

First Known Use

1914, in the meaning defined above

Time Traveler
The first known use of galactosidase was in 1914

Dictionary Entries Near galactosidase

Cite this Entry

“Galactosidase.” Dictionary, Merriam-Webster, Accessed 2 Oct. 2023.

Medical Definition


ga·​lac·​to·​si·​dase gə-ˌlak-ˈtō-sə-ˌdās, -zə-ˌdāz How to pronounce galactosidase (audio)
: an enzyme (as lactase) that hydrolyzes a galactoside

More from Merriam-Webster on galactosidase

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