methylation

noun

meth·​yl·​a·​tion ˌme-thə-ˈlā-shən How to pronounce methylation (audio)
: the introduction of a methyl radical into a substance
The methylation of metals (that is, the substitution of a metal atom for the hydrogen atom of the hydroxyl group of a methyl alcohol molecule) can result in the metal's becoming volatile.— Corale L. Brierley
especially : dna methylation
As cells begin to specialize into adult tissues, methylation seems to inactivate genes that are no longer needed. — John Travis

Examples of methylation in a Sentence

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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
To quantify these changes, the team used epigenetic clocks, tools that estimate biological age based on methylation patterns. — Brian Mastroianni, Health, 10 Mar. 2025 Facing infant cuteness: How nurturing care motivation and oxytocin system gene methylation are associated with responses to baby schema features The Conversation. — Avery Hurt, Discover Magazine, 24 Feb. 2025 Here the researchers propose their radical theory – mutations are possibly the upstream driver of DNA methylation. — New Atlas, 2 Feb. 2025 Vegan Diet Reduces Biological Age Markers Overall, the twins who went vegan saw a significant reduction in markers of biological age based on changes in DNA methylation. — Lisa Rapaport, EverydayHealth.com, 29 July 2024 See All Example Sentences for methylation

Word History

First Known Use

1855, in the meaning defined above

Time Traveler
The first known use of methylation was in 1855

Phrases Containing methylation

Rhymes for methylation

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“Methylation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/methylation. Accessed 21 Mar. 2025.

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Medical Definition

methylation

noun
meth·​yl·​ation ˌmeth-ə-ˈlā-shən How to pronounce methylation (audio)
: introduction of the methyl group into a chemical compound
especially : dna methylation
methylate
ˈmeth-ə-ˌlāt How to pronounce methylation (audio)
transitive verb
methylated; methylating
Last Updated: - Updated example sentences
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