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amniotic sac

n.
  1. amnion
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
amniotic sac in Science

amniotic sac

  1. See amnion.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
amniotic sac in Culture

amniotic sac

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.)

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.