# methylation

> English word · Noun · IPA /ˌmɛθɪˈleɪʃən/ · frequency rank #32,502

## Definitions
1. The addition of a methyl group to a molecule.
2. The addition of a methyl group to cytosine and adenine residues in DNA that leads to the epigenetic modification of DNA and the reduction of gene expression and protein production.

## Etymology
From methyl + -ation.

## Common misspellings (18)
`emthylation`, `mehtylation`, `methhylation`, `methlyation`, `methyaltion`, `methylaiton`, `methylasion`, `methylatino`, `methylationn`, `methylatoin`, `methylattion`, `methyllation`, `methyltaion`, `methyylation`, `metthylation`, `metyhlation`, `mmethylation`, `mtehylation`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/methylation