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The third and final excretory organ that develops in a vertebrate embryo. In birds, reptiles, and mammals it replaces the mesonephros as the functional excretory organ and develops into the adult kidney.
[meta- + Greek nephros, kidney.]
met′a·neph′ric (-rĭk) adj.
n, pl -roi (-rɔɪ)
[C19: New Latin, from meta- + Greek nephros kidney]
met•a•neph•ros(ˌmɛt əˈnɛf rɒs)
n., pl. -roi (-roi).
an embryonic excretory organ of reptiles, birds, and mammals, which develops into the functional kidney.
[1875–80; meta- + Greek nephrós kidney]