fe·​tus | \ ˈfē-təs How to pronounce fetus (audio) \

Definition of fetus

: an unborn or unhatched vertebrate especially after attaining the basic structural plan of its kind specifically : a developing human from usually two months after conception to birth — compare embryo sense 1a

Examples of fetus in a Sentence

Recent Examples on the Web The placenta nourishes a developing fetus and tries to block damaging substances in the mother’s bloodstream. Washington Post, "Study finds air pollution reaches placenta during pregnancy," 17 Sep. 2019 Coal combustion also produces mercury—a neurotoxin for fetuses. Emily Holden, Scientific American, "Climate Change Is Having Widespread Health Impacts," 16 Sep. 2019 Additionally, some experts believe fetuses that are exposed to unusually high testosterone levels while in the womb (like if the pregnant person has PCOS or diabetes) may be more inclined to develop this disorder, Redman says. Mary Claire Lagroue, SELF, "Why Is PCOS Still So Hard for Doctors to Understand?," 12 Sep. 2019 That first day of class in August, we were told our adoption process would commence by naming our fetuses. Liv Mcconnell, Teen Vogue, "What Spiritual Adoption of a Fetus in High School Really Taught Me," 23 Aug. 2019 At the end of June, Alabama news outlets reported that Jones, a 27-year-old Birmingham resident, had been taken into police custody after a grand jury indicted her on manslaughter charges for the death of her then-5-month-old fetus. P.r. Lockhart, Vox, "The Alabama woman indicted after a miscarriage will not be prosecuted," 3 July 2019 Also, in what’s called congenital syphilis, a pregnant person can pass the infection to their fetus. Carolyn L. Todd, SELF, "We Need to Talk About Syphilis," 28 May 2019 That would require directly sampling the hormone in utero, which can endanger a developing fetus. Emily Underwood, Science | AAAS, "Study challenges idea that autism is caused by an overly masculine brain," 3 Sep. 2019 These tests are often used, for example, to detect the telltale signs of Down syndrome in a developing fetus. San Diego Union-Tribune, "With Illumina and Google ties, San Diego startup Cradle Genomics gets $17M," 16 July 2019

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

14th century, in the meaning defined above

History and Etymology for fetus

Middle English, from Latin, act of bearing young, offspring; akin to Latin fetus newly delivered, fruitful — more at feminine

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Statistics for fetus

Last Updated

24 Oct 2019

Time Traveler for fetus

The first known use of fetus was in the 14th century

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More Definitions for fetus


How to pronounce fetus (audio)

English Language Learners Definition of fetus

: a human being or animal in the later stages of development before it is born


fe·​tus | \ ˈfē-təs How to pronounce fetus (audio) \

Kids Definition of fetus

: an animal not yet born or hatched but more developed than an embryo


variants: or chiefly British foetus \ ˈfēt-​əs How to pronounce foetus (audio) \
plural fetuses or chiefly British foetuses or foeti\ ˈfēt-​ˌī How to pronounce foeti (audio) \

Medical Definition of fetus

: an unborn or unhatched vertebrate especially after attaining the basic structural plan of its kind specifically : a developing human from usually two months after conception to birth — compare embryo

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More from Merriam-Webster on fetus

Rhyming Dictionary: Words that rhyme with fetus

Spanish Central: Translation of fetus

Nglish: Translation of fetus for Spanish Speakers

Britannica English: Translation of fetus for Arabic Speakers

Britannica.com: Encyclopedia article about fetus

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