mesonephros
noun
me·so·neph·ros ˌme-zə-ˈne-frəs 
ˌmē-,
-sə-,
-ˌfräs
plural mesonephroi ˌme-zə-ˈne-ˌfrȯi
ˌmē-,
-sə-
: either member of the second and midmost of the three paired vertebrate renal organs that functions in adult fishes and amphibians but functions only in the embryo of reptiles, birds, and mammals in which it is replaced by a metanephros in the adult compare metanephros, pronephros
mesonephric
ˌme-zə-ˈne-frik
adjective ˌmē-
-sə-
Word History
Etymology
New Latin, from mes- + Greek nephros kidney — more at nephritis
First Known Use
1877, in the meaning defined above
Medical Definition
mesonephros
noun
me·so·neph·ros ˌmez-ə-ˈnef-rəs ˌmēz-
ˌmēz- ˌmēs-,
ˌmes-,
-ˌräs
plural mesonephroi -ˌrȯi
: either member of the second and midmost of the three paired vertebrate renal organs that functions in adult fishes and amphibians but functions only in the embryo of reptiles, birds, and mammals in which it is replaced by a metanephros in the adult
called also Wolffian body
compare pronephros