plural noun Ne·re·idae \nə̇ˈrēəˌdē\

Definition of Nereidae

  1. :  a large family of predaceous marine polychaete worms that have an elongated many-segmented body with large complex parapodia on most segments and a well-defined head with paired tentacles and palps, four prostomial eyes, eight peristomial cirri, and large jaws which bite transversely and that include burrowing and free-swimming forms — see nereis

Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Join MWU now and get access to America’s largest dictionary, with:

  • 300,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

Origin and Etymology of nereidae

New Latin, from Nereis, type genus + -idae

Seen and Heard

What made you want to look up Nereidae? Please tell us where you read or heard it (including the quote, if possible).


feeling or affected by lethargy

Get Word of the Day daily email!