extraembryonic
/ˌɛkstrəˌɛmbriˈɑnɪk/
adjective
- Relating to structures or tissues that develop outside the embryo but support its growth, such as the placenta or amniotic sac.
- The placenta is an important extraembryonic organ.
- The extraembryonic membranes protect the developing embryo.
- Scientists study extraembryonic tissues to understand early development.