te·​rato·​gen | \ tə-ˈra-tə-jən How to pronounce teratogen (audio) \

Definition of teratogen

: a teratogenic agent

Examples of teratogen in a Sentence

Recent Examples on the Web

The science of teratogens While much is now known about alcohol and its impact on a developing fetus, there’s more to learn. Anchorage Daily News, "‘He looks so normal’: When it comes to FASDs, there’s no such thing as predictability," 24 June 2019 According to Levin, these results show that the brain protects the developing body against drugs that otherwise might be dangerous teratogens (compounds that cause birth defects). Adam Rogers, WIRED, "Brainless Embryos Suggest Bioelectricity Guides Growth," 18 Mar. 2018 Some substances, known as teratogens, are perfectly fine for adults but are toxic for developing fetuses. Yvette D'entremont, SELF, "Don’t Buy Into Toxic 'Toxin-Free' Marketing," 13 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'teratogen.' 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 teratogen

1959, in the meaning defined above

History and Etymology for teratogen

terato- + -gen, after teratogenic

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Statistics for teratogen

Last Updated

28 Jun 2019

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Time Traveler for teratogen

The first known use of teratogen was in 1959

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More Definitions for teratogen


te·​rato·​gen | \ tə-ˈrat-ə-jən How to pronounce teratogen (audio) \

Medical Definition of teratogen

: a teratogenic agent (as a drug or virus)

More from Merriam-Webster on teratogen

Nglish: Translation of teratogen for Spanish Speakers

Comments on teratogen

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


appealing forcibly to the mind or reason

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