mesonephros
/ˌmɛsə(ʊ)ˈnɛfrɒs/(also mesonephron) Anatomy and Zoology
noun
The part of the nephrogenic tissue of a vertebrate embryo that develops after the pronephros and forms the adult kidney of fishes and amphibians, but is succeeded by the metanephros in humans and other amniotes and persists only as the epididymis (in males) and the epoophoron (in females).
Origin
Late 19th century; earliest use found in Ray Lankester (1847–1929), zoologist. From meso- + ancient Greek νεϕρός kidney. In form mesonephron after ancient Greek nouns in -ον. Compare French mésonéphros. Compare the parallel formations metanephros, pronephros.