A worm of the family Naididae, which comprises small aquatic (mostly freshwater) oligochaetes.
Belonging to, characteristic of, or designating the family Naididae of worms.
1930s; earliest use found in Ecological Monographs. From scientific Latin Naididae, family name from Naid-, stem of Nais, genus name + -idae. Compare German Naididen, plural.