Nereid

In Greek mythology, the Nereids or Nereides ( NEER-ee-idz; Ancient Greek: Νηρηΐδες, romanized: Nērēḯdes; sg. Νηρηΐς, Nērēḯs, also Νημερτές) are sea nymphs (female spirits of sea waters), the 50 daughters of the 'Old Man of the Sea' Nereus and the Oceanid Doris, sisters to their brother Nerites. They often accompany Poseidon, the god of the sea, and can be friendly and helpful to sailors (such as the Argonauts in their search for the Golden Fleece).