fetus

noun

fe·​tus ˈfē-təs How to pronounce fetus (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Other existing Idaho laws on miscarriage management are limited, mostly focused on the disposal of a fetus’s remains and on vital statistics certificates. — Sarah Cutler, Idaho Statesman, 23 Oct. 2026 After her death, DNA results revealed that Pickard was the father of Birchmore's unborn fetus, not Farwell. — Matt Schooley, CBS News, 21 Oct. 2026 If there’s a measles infection during pregnancy, the measles virus can pass to a fetus in utero or can transmit during or just after birth, leading to a congenital case. — Beth Mole, ArsTechnica, 19 Oct. 2026 Because the situation put her at high risk of developing an infection, medical experts said doctors should have offered to speed up delivery or empty her uterus; the fetus was not viable, and losing the pregnancy was inevitable. — Cassandra Jaramillo, ProPublica, 19 Oct. 2026 See All Example Sentences for fetus

Word History

Etymology

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

First Known Use

14th century, in the meaning defined above

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

Rhymes for fetus

See All Rhymes for fetus

Browse Nearby Words

fettuccine Alfredo
fetus
feu
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Cite this Entry

“Fetus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fetus. Accessed 28 Oct. 2026.

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Kids Definition

fetus

noun
fe·​tus ˈfēt-əs How to pronounce fetus (audio)
plural fetuses
: a young animal while in the body of its mother or in the egg especially in the later stages of development
especially : a developing human being in the uterus from usually two months after pregnancy occurs to birth compare embryo sense 1

Medical Definition

fetus

noun
fe·​tus
variants or chiefly British foetus
ˈfēt-əs How to pronounce fetus (audio)
plural fetuses or chiefly British foetuses or foeti ˈfēt-ˌī How to pronounce fetus (audio)
: 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

More from Merriam-Webster on fetus

Britannica.com: Encyclopedia article about fetus

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