(in many invertebrate animals) a tubule open to the exterior that acts as an organ of excretion or osmoregulation. It typically has ciliated or flagellated cells and absorptive walls.
- ‘Each segment typically contains a pair of nephridia.’
- ‘The organs they produce include segmental muscles, nephridia, gonads and gonoducts.’
- ‘Torsion in gastropods has the unfortunate result that wastes are expelled from the gut and nephridia near the gills.’
- ‘Gametes are shed into the coelom and carried outside the body through the nephridia or as a result of the body wall actually rupturing.’
- ‘Sperm is also released through the nephridium.’
Late 19th century: modern Latin, from Greek nephrion (diminutive of nephros kidney) + the diminutive ending -idium.