Origin of nephridium
First Known Use: 1877
Medical Definition of nephridium
plural -ia \-ē-ə\play
: an excretory organ that is characteristic of various coelomate invertebrates (as annelid worms, mollusks, brachiopods, and some arthropods), occurs paired in each body segment or as a single pair serving the whole body, typically consists of a tube opening at one end into the coelom and discharging at the other end on the exterior of the body, is often lengthened and convoluted, and has glandular walls
Seen and Heard
What made you want to look up nephridium? Please tell us where you read or heard it (including the quote, if possible).