amniotic sac

American  

[am-nee-aht-ik sak] / ˌæm niˈɑt ɪk ˈsæk /

noun

1. Embryology. amnion or bag of waters.

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amniotic sac Scientific  

1. See amnion

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amniotic sac Cultural  

1. A two-layered membrane that surrounds the embryo or fetus in the uterus. The amniotic sac is filled with fluid in which the embryo or fetus is suspended. (See reproductive systems.)

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Example Sentences

In a dark room, a doctor pointed to an hourglass shape glowing on the ultrasound screen: There was her amniotic sac, funneling into her dilated cervix, and there was their tiny daughter’s foot, dipping out.

From Salon • May 27, 2026

Then came the worst part: I passed the amniotic sac.

From The Wall Street Journal • May 13, 2026

At the hospital, Nusslock said she was diagnosed with a premature rupture of the membrane of the amniotic sac — a dangerous complication in which an abortion is a recommended treatment.

From Los Angeles Times • Sep. 30, 2024

Sharing the placenta and amniotic sac only occurs in about one in 5,000 - 6,000 pregnancies.

From BBC • Jun. 12, 2023

Leonard Hayflick had an especially personal connection with his cell line, WISH, which Gartler had listed as contaminated: he’d grown it using cells from the amniotic sac in which his unborn daughter had once floated.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot