pronephros

noun

pro·​neph·​ros (ˌ)prō-ˈne-frəs How to pronounce pronephros (audio)
-ˌfräs
: either member of the first and most cranial pair of the three successive paired vertebrate renal organs that functions in the adults of amphioxus and some lampreys, functions temporarily in larval fishes and amphibians, and is present but nonfunctional in embryos of reptiles, birds, and mammals compare mesonephros, metanephros
pronephric adjective

Word History

Etymology

New Latin, from Greek pro- + nephros kidney — more at nephritis

First Known Use

1877, in the meaning defined above

Time Traveler
The first known use of pronephros was in 1877

Dictionary Entries Near pronephros

Cite this Entry

“Pronephros.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pronephros. Accessed 28 Mar. 2024.

Medical Definition

pronephros

noun
pro·​neph·​ros (ˈ)prō-ˈnef-rəs, -ˌräs How to pronounce pronephros (audio)
plural pronephroi -ˌrȯi How to pronounce pronephros (audio)
: either member of the first and most cranial pair of the three paired vertebrate renal organs that functions in the adults of amphioxus and some lampreys, functions temporarily in larval fishes and amphibians, and is present but nonfunctional in embryos of reptiles, birds, and mammals compare mesonephros, metanephros

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