nephridium

(redirected from Protonephridium)
Also found in: Medical, Encyclopedia.
Related to Protonephridium: Metanephridium, Protonephridia

ne·phrid·i·um

 (nə-frĭd′ē-əm)
n. pl. ne·phrid·i·a (-ē-ə)
1. A tubular excretory organ in many invertebrates, such as mollusks and earthworms.
2. The excretory organ of a vertebrate embryo from which the kidney develops.

[nephr(o)- + Latin -idium, diminutive suff. (from Greek -idion).]

ne·phrid′i·al adj.

nephridium

(nɪˈfrɪdɪəm)
n, pl -ia (-ɪə)
(Zoology) a simple excretory organ of many invertebrates, consisting of a tube through which waste products pass to the exterior
[C19: New Latin: little kidney]
neˈphridial adj

ne•phrid•i•um

(nəˈfrɪd i əm)

n., pl. -phrid•i•a (-ˈfrɪd i ə)
an excretory tubule in annelids, mollusks, and other invertebrates that discharges wastes from the body cavity through a pore on the body surface.
[1875–80; < Greek nephr(ós) kidney]
ne•phrid′i•al, adj.
Mentioned in ?