1. plural of chorion; the outermost membranes that surround developing embryos in reptiles, birds, and mammals
Usage: biological term

Examples

• The chorions of bird eggs provide protection and gas exchange for the developing chicks.
• Scientists studied the chorions from multiple mammalian species to understand embryonic development.
• The chorions help regulate the exchange of nutrients and waste products during pregnancy.
• Researchers examined the chorions under a microscope to identify any abnormalities.
• The chorions of reptile eggs are typically more leathery than those of birds.
• Medical students learned about the structure and function of chorions in their embryology class.