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methyl

1 American  
[meth-uhl] / ˈmɛθ əl /

adjective

Chemistry.
  1. containing the methyl group. Me


methyl- 2 American  
  1. a combining form occurring in the names of chemical compounds in which the methyl group is present.

    methylamine.


methyl British  
/ ˈmiːθaɪl, ˈmɛθɪl, məˈθɪlɪk /

noun

  1. (modifier) of, consisting of, or containing the monovalent group of atoms CH 3

  2. an organometallic compound in which methyl groups are bound directly to a metal atom

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

methyl Scientific  
/ mĕthəl /
  1. The radical CH 3, derived from methane.


Other Word Forms

  • methylic adjective

Etymology

Origin of methyl

First recorded in 1835–45; by back formation from methylene

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Many genetic conditions involve genes that are improperly turned on or off, and adjusting methyl groups may provide a way to correct those problems without damaging DNA.

From Science Daily • Jan. 5, 2026

The second step is methylation, which attaches a methyl group to the sugar.

From Science Daily • Jan. 1, 2026

When levels of methyl oleate fall, workers detect the change and begin preparing to replace her.

From Science Daily • Nov. 22, 2025

In 2018, for instance, the FDA withdrew authorization for certain synthetic flavors—including benzophenone, ethyl acrylate, and eugenyl methyl ether—used to mimic flavors like mint, cinnamon and citrus in processed foods.

From Salon • Jan. 23, 2025

Wood is strongly heated in an iron still, and the methyl alcohol is given off in the form of vapour, which on being collected and cooled condenses into liquid.

From Marvels of Scientific Invention An Interesting Account in Non-technical Language of the Invention of Guns, Torpedoes, Submarine Mines, Up-to-date Smelting, Freezing, Colour Photography, and many other recent Discoveries of Science by Corbin, Thomas W.