: a free-swimming dimorphic sexual individual of certain polychaete worms (family Nereidae) characterized by greatly enlarged eyes, enlarged and modified parapodia and other appendages, and more or less complete obliteration of the internal viscera by masses of developing germ cells

Word History


New Latin, from heter- + Nereis

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Dictionary Entries Near heteronereis

Cite this Entry

“Heteronereis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heteronereis. Accessed 26 Feb. 2024.

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