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Related to metanephros: pronephros, mesonephros


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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


n, pl -roi (-rɔɪ)
(Zoology) the last-formed posterior part of the embryonic kidney in reptiles, birds, and mammals, which remains functional in the adult. See also pronephros, mesonephros
[C19: New Latin, from meta- + Greek nephros kidney]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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]
met`a•neph′ric, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Am, amniotic cavity; db, decidua basalis; L, Labyrinth; Mt, metanephros; Ms, mesonephros.
Among the neoplasms, Wilms tumor is the commonest renal tumor of childhood representing approximately 10% of all childhood malignancies that arises from embryological precursors of renal parenchyma (metanephros) with a peak incidence between 3-4 years; it is uncommon above the age of 5 and is rare in neonates1.
Pronephros, mesonephros, and metanephros represent the three primitive kidneys, present during the various developmental stages of the human embryo.
According to the most accepted theory, the kidney reaches the adult location at the eighth gestational week followed by the superior accelerated migration of the metanephros and the delay in mesonephros involution before completing the diaphragmatic development, that is, before the fusion of the pleuroperitoneal membrane.
In this study, we aimed to explore the effects of CsA on metanephros development in the pregnant BALB/c mice.
As the kidney ascends, the arterial degeneration begins at the cephalad end of the metanephros, the segmental branch to the lower pole is the one most likely to persist as an accessory vessel (Graves 1969).
This set of genes is known to have a direct effect on the process of cell proliferation involved in metanephros development of the kidney.
The embryologic explanation of these variations has been presented and discussed by Felix.[sup][8] According to him, the developing mesonephros, metanephros, and gonads are supplied by nine pairs of lateral mesonephric arteries arising from the dorsal aorta.
The future kidney that is the metanephros was observed for changes and diameter and epithelial height of proximal tubules was measured at 40X after calibrating ocular micrometer (Figure 1).