fetus

noun

fe·​tus ˈfē-təs 

: 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 complaint said an autopsy placed the age of her fetus at between 19 and 20 weeks. —Mark Harper, USA Today, 19 Aug. 2025

On June 18, Maddox’s fetus died and she was readmitted to the hospital, where she was diagnosed with sepsis. —Marlene Lenthang, NBC news, 18 Aug. 2025

The legacy of hunger and trauma is remembered in our cells Malnutrition can also harm fetuses still developing in the womb, according to health experts. —Juliana Kim, NPR, 29 July 2025

If the fetus makes it through a birth, good luck with health care, food and housing, or making it through what used to be called childhood diseases and now will be childhood killers. —Chicago Tribune, 24 July 2025

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

Rhymes for fetus

• foetus
• meatus
• thetis
• treatise
• caritas
• civitas
• cellulitis
• margaritas
• tonsillitis

Kids Definition

fetus

noun

fe·​tus ˈfēt-əs 

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 

plural fetuses or chiefly British foetuses or foeti ˈfēt-ˌī 

: 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