nephrostome
/ˈnɛfrə(ʊ)stəʊm/Zoology and Embryology
noun
The opening, typically funnel-shaped and ciliated, between the coelom and a nephridium or nephric tubule.
Origin
Late 19th century; earliest use found in George Rolleston (1829–1881), physician and physiologist. From nephro- + -stome, probably after German Nephrostom.