metanephros
/ˌmɛtəˈnɛfrɒs/
noun
- The third and most advanced stage of kidney development in vertebrates, which becomes the permanent kidney in mammals, reptiles, and birds.
- The metanephros eventually develops into the adult kidney with its filtering units.
- Unlike the earlier pronephros, the metanephros is more complex and efficient.
- In human embryos, the metanephros begins to form around the fifth week of pregnancy.