mu·​ta·​gen | \ ˈmyü-tə-jən \

Definition of mutagen

: an agent (such as a chemical or various radiations) that tends to increase the frequency or extent of mutation

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Other Words from mutagen

mutagenic \ ˌmyü-​tə-​ˈje-​nik \ adjective
mutagenically \ -​ni-​k(ə-​)lē \ adverb

Examples of mutagen in a Sentence

Recent Examples on the Web

The fallout leads to three samples of an experimental mutagen dropping through the atmosphere and landing on Earth, where a wolf, an alligator, and George are all infected. Tasha Robinson, The Verge, "Rampage is laughably dumb, but at least there’s plenty of rampaging," 11 Apr. 2018 The main villain is not Shredder, but instead a cat named Old Hob, who was also transformed by the same mutagen that brought The Turtles to their current state. Dak, WIRED, "GeekMom: Comic Book Corner — June 20th, 2012," 20 June 2012

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

First Known Use of mutagen

1933, in the meaning defined above

History and Etymology for mutagen

International Scientific Vocabulary mutation + -gen

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Time Traveler for mutagen

The first known use of mutagen was in 1933

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More Definitions for mutagen


mu·​ta·​gen | \ ˈmyüt-ə-jən \

Medical Definition of mutagen

: a substance (as a chemical or various radiations) that tends to increase the frequency or extent of mutation

More from Merriam-Webster on mutagen Encyclopedia article about mutagen

Comments on mutagen

What made you want to look up mutagen? Please tell us where you read or heard it (including the quote, if possible).


to gather or build up little by little

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