ne·​phrid·​i·​um ni-ˈfri-dē-əm How to pronounce nephridium (audio)
plural nephridia ni-ˈfri-dē-ə How to pronounce nephridium (audio)
: a tubular glandular excretory organ characteristic of various invertebrates
nephridial adjective

Word History


New Latin

First Known Use

1877, in the meaning defined above

Time Traveler
The first known use of nephridium was in 1877

Dictionary Entries Near nephridium

Cite this Entry

“Nephridium.” Dictionary, Merriam-Webster, Accessed 25 Mar. 2023.

Medical Definition


ne·​phrid·​i·​um ni-ˈfrid-ē-əm How to pronounce nephridium (audio)
plural nephridia -ē-ə How to pronounce nephridium (audio)
: 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
nephridial adjective

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