meth·​yl·​a·​tion | \ ˌme-thə-ˈlā-shən How to pronounce methylation (audio) \

Definition of methylation

: 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

First Known Use of methylation

1855, in the meaning defined above

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The first known use of methylation was in 1855

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Cite this Entry

“Methylation.” The Dictionary, Merriam-Webster Inc., Accessed 15 December 2019.

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meth·​yl·​ation | \ ˌmeth-ə-ˈlā-shən How to pronounce methylation (audio) \

Medical Definition of methylation

: introduction of the methyl group into a chemical compound especially : dna methylation

Other Words from methylation

methylate \ ˈmeth-​ə-​ˌlāt How to pronounce methylate (audio) \ transitive verb methylated; methylating

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