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

Amniotic fluid, which is contained within the amniotic sac, supports, cushions and protects a developing fetus.

From Los Angeles Times • Apr. 12, 2025

The chance of losing twins with the same placenta and amniotic sac - monochorionic monoamniotic - is 54 times higher than a single baby pregnancy in the first 24 weeks.

From BBC • Jun. 12, 2023

For instance, many women experience premature rupture of membranes, during which the amniotic sac ruptures before viability.

From Slate • Aug. 24, 2022

Membranes in the fluid-filled amniotic sac that surrounds the fetus often rupture or break at the start of childbirth - commonly called water breaking.

From Washington Times • Aug. 22, 2022

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