• (n.) Any annelid resembling Nereis, or of the family Lycoridae or allied families. • (n.) Any annelid resembling Nereis, or of the family Lycoridae or allied families. Found on http://thinkexist.com/dictionary/meaning/nereidian/
Ne`re·id'i·an noun (Zoology) Any annelid resembling Nereis, or of the family Lycoridæ or allied families. Found on http://www.encyclo.co.uk/webster/N/15