1. Plural of nephridium; small tubular excretory organs found in many invertebrates (such as earthworms and mollusks) that function similarly to kidneys in removing waste products.
Usage: biology; plural form; technical

Examples

• Earthworms use their nephridia to filter waste from their body fluids.
• The nephridia of marine worms help regulate salt and water balance.
• In biology class, students learned how nephridia function as primitive kidneys in invertebrates.
• Each segment of an annelid worm typically contains a pair of nephridia.
• The structure of nephridia varies among different species of mollusks.