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

One petition would ban abortions once cardiac activity is detected in a fetus. Kathleen Gray, Detroit Free Press, "Abortion opponents ready to start petition drives to restrict first, second trimester abortions," 19 June 2019 Between 1999 and 2014 in the United States, more than 18,400 infants were born through gestational surrogacy, where the carrier is not related to the fetus. Vivian Wang, New York Times, "Surrogate Pregnancy Battle Pits Progressives Against Feminists," 12 June 2019 But sampling hormones in an early fetus can endanger a pregnancy. Mitch Leslie, Science | AAAS, "Talk to the hand. Scientists try to debunk idea that finger length can reveal personality and health," 6 June 2019 Since this strength is important for pregnancy, and essential for a growing fetus, Wakayama wanted to see if mice could even become pregnant under these conditions. Amber Jorgenson, Discover Magazine, "Sex and the Cosmic City," 18 Apr. 2019 The virus, according to the report, can infect the layer of cells in the placenta that's responsible for delivering nutrients to the fetus. Macaela Mackenzie, Glamour, "Rift Valley Fever Could Be the Next Global Health Crisis For Pregnant Women," 10 Jan. 2019 But one of the top stories of 2017 was the success of one group in making artificial wombs a reality—at least for lamb fetuses in later stages of their gestation. Everyday Einstein Sabrina Stierwalt, Scientific American, "Could Artificial Wombs Be a Reality?," 24 Jan. 2018 Another pressing question is how the placenta, a tissue with such a remarkable ability to withstand infection that only a small number of pathogens are known to cross from the mother to the fetus, lets Zika through. Quanta Magazine, "New Insights Into How Zika Harms the Brain," 7 July 2016 Alabama is among 38 states with laws that classify fetuses as victims in homicide or assault, according to the National Conference of State Legislatures. The Washington Post, The Mercury News, "A bullet, a miscarriage and an unthinkable question: Who’s the victim, and who is to blame?," 29 June 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

18 Jul 2019

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Time Traveler for fetus

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

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More Definitions for fetus



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

Comments on fetus

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


something desired as essential

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