nephridium

A tubular excretory organ in many invertebrates, such as mollusks and earthworms.

The excretory organ of a vertebrate embryo from which the kidney develops.

The sexual or renal organ of mollusks, corresponding to the kidneys of the vertebrates, having an excretory and depurative office; the so-called organ of Bojanus.

A segmental tubule; one of the tubules of the primitive urinogenital organs; a segmental organ. See Illust. under loeven’s larva.

a tubular excretory organ in some invertebrates

the embryonic excretory organ that develops into the kidney