pronephros
noun
pro·neph·ros
(ˌ)prō-ˈne-frəs 
-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
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“Pronephros.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pronephros. Accessed 4 Nov. 2025.
Copy CitationMedical Definition
pronephros
noun
pro·neph·ros
(ˈ)prō-ˈnef-rəs, -ˌräs
plural pronephroi
-ˌrȯi
: 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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