Nereid

In Greek mythology, the Nereids ( /ˈnɪəriɪdz/ NEER-ee-idz; Ancient Greek: Νηρηΐδες, sg. Νηρηΐς) are sea nymphs (female spirits of sea waters), the fifty daughters of Nereus and Doris, sisters to Nerites. They were distinct from the mermaid-like Sirens. They often accompany Poseidon and can be friendly and helpful to sailors fighting perilous storms.