meth·​yl | \ ˈme-thəl How to pronounce methyl (audio) \

Definition of methyl

: an alkyl radical CH3 derived from methane

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Other Words from methyl

methylic \ mə-​ˈthi-​lik How to pronounce methylic (audio) \ adjective

Examples of methyl in a Sentence

Recent Examples on the Web

The board voted 4-0 to implement a reduced rate increase by taking $150,000 from a fund reserved for cleaning water that has been contaminated by methyl tert-butyl ether, or MTBE, a volatile organic compound. Alejandra Reyes-velarde,, "Crescenta Valley Water District implements lower rate increase than proposed," 28 June 2018 These cave fish have elevated levels of an enzyme that adds methyl groups to DNA compared to surface fish. Diana Gitig, Ars Technica, "An evolutionary adaptation that doesn’t directly rely on new mutations," 1 June 2018 Methylation is the process by which cells attach chemicals called methyl groups to DNA molecules. Avery Thompson, Popular Mechanics, "Living in Space Changes Your DNA, NASA Finds," 27 Oct. 2017 The latter refers to the addition of chemical tags to DNA called methyl groups that affect genetic activity, but don’t change the underlying sequence. Bradley J. Fikes,, "Singlera Genomics raises $60 million for early stage cancer tests," 30 Mar. 2018 One of the best studied is a molecular cap called a methyl group. Carl Zimmer, New York Times, "The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars," 31 Jan. 2018 Caldwell used a patented hazer device that emits methyl anthranilate at precise levels. Ruth Brown, idahostatesman, "What’s one solution to control crows in Downtown Nampa? Allow police to shoot them.," 8 Dec. 2017 One common chemical plant defense is the release of the foul-tasting substance methyl jasmonate. Ben Panko, Smithsonian, "Strong Plant Defenses Made These Hungry Caterpillars Eat Each Other," 11 July 2017 Along with being a pollutant, mercury is a naturally occurring element (often occurring in nature naturally bonded to methyl, hence methyl mercury). Annie Behr, Slate Magazine, "The Scales Have Tipped on Fish and Pregnancy," 20 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'methyl.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of methyl

1840, in the meaning defined above

History and Etymology for methyl

International Scientific Vocabulary, back-formation from methylene

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Time Traveler for methyl

The first known use of methyl was in 1840

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More Definitions for methyl


meth·​yl | \ ˈmeth-əl, British also ˈmē-ˌthīl\

Medical Definition of methyl

: an alkyl group CH3 that is derived from methane by removal of one hydrogen atom

Other Words from methyl

methylic \ mə-​ˈthil-​ik How to pronounce methylic (audio) \ adjective

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More from Merriam-Webster on methyl

Rhyming Dictionary: Words that rhyme with methyl

Nglish: Translation of methyl for Spanish Speakers Encyclopedia article about methyl

Comments on methyl

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a shady place in a garden or forest

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