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 1b

Examples of fetus in a Sentence

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So that means the fetus is exposed to THC, and the concerns about marijuana’s health effects during pregnancy and lactation stem mainly from this fact. Julia Belluz, Vox, "More pregnant women are using marijuana. We don’t know if that’s safe.," 20 Nov. 2018 To allow the implantation and development of a fetus that could be construed as a foreign invader, the immune system needs to selectively ease its normal level of vigilance. Melissa Healy, The Seattle Times, "Pregnancy and childbirth may protect some women from developing dementia," 23 July 2018 One method for controlling the waterfowl population includes oiling goose eggs with food-grade corn oil, which seals the egg's pores and prevents the bird fetus inside from developing further, according to the U.S. Department of Agriculture. Evan Frank, Milwaukee Journal Sentinel, "Lac La Belle will have a goose roundup again this year," 21 Mar. 2018 Pregnant women who develop influenza have an eight-fold increased risk of complications, including death, as well as complications for the fetus, such as stillbirth. Tara C. Smith, SELF, "No, the Flu Shot Is Not 100 Percent Effective. Yes, You Still Need It," 27 Sep. 2018 To make these new experimental blood tests, the Quake team identified and zeroed in on the activity levels of specific genes in the fetus or its placenta. Dina Fine Maron, Scientific American, "Blood Test Could Predict Premature Birth Risk, Due Date," 7 June 2018 Bone-marrow transplants in fetuses, sometimes using the father as a donor, were first tried in the 1990s. New York Times, "Five Blood Transfusions, One Bone Marrow Transplant — All Before Birth," 25 May 2018 In fetuses and infants, this protein, as its name suggests, promotes nerve growth. Brian Gormley, WSJ, "The Heated Quest for Opioid Alternatives," 25 May 2018 Nevertheless, Dr Nakauchi and his group have followed up their mouse work by growing human pancreas cells in pig fetuses. The Economist, "Stem cells and gene editingUsing domestic animals to make human organs," 22 Feb. 2018

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

14 Mar 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).


of or relating to a parable or parabola

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