uterus

noun

uter·​us ˈyü-tə-rəs 

ˈyü-trəs

plural uteri ˈyü-tə-ˌrī  or uteruses

1

: a muscular organ of the female mammal for containing and usually for nourishing the young during development prior to birth

called also womb

2

: a structure in some lower animals analogous to the uterus in which eggs or young develop

Examples of uterus in a Sentence

Recent Examples on the Web

Because endometriosis involves tissue from the endometrium, or the inner lining of the uterus, growing outside of the uterus, it’s typically formally diagnosed via a laparoscopic procedure that can show the locations of the endometriosis lesions. —Mara Santilli, Flow Space, 2 July 2025

For instance, Black women often experience fibroids, or benign growths in the uterus, at higher rates than white women, according to a recent study in the American Journal of Obstetrics and Gynecology. —Megan Myscofski, NPR, 1 July 2025

Castor oil may cause contractions (when muscles tighten and relax) in the uterus. —Lindsay Curtis, Health, 25 June 2025

At the same time, the tissue lining your uterus (a.k.a. —Julia Ries, SELF, 23 June 2025

Word History

Etymology

Middle English, from Latin, belly, womb; probably akin to Greek hoderos belly, Sanskrit udara

First Known Use

14th century, in the meaning defined at sense 1

Kids Definition

uterus

noun

uter·​us ˈyüt-ə-rəs 

plural uteruses or uteri -ˌrī 

: the muscular organ of a female mammal in which the young develop before birth

called also womb

Medical Definition

uterus

noun

uter·​us ˈyüt-ə-rəs 

plural uteri -ˌrī  also uteruses

: an organ in female mammals for containing and usually for nourishing the young during development prior to birth that consists of a greatly modified and enlarged section of an oviduct (as in rodents and marsupials) or of the two oviducts united (as in the higher primates including humans), that has thick walls consisting of an outer serous layer, a very thick middle layer of smooth muscle, and an inner mucous layer containing numerous glands, and that during pregnancy undergoes great increase in size and change in the condition of its walls

called also womb

see cervix sense 2a, corpus uteri, endometrium, fundus sense c, myometrium, perimetrium