Hydriad is a rare term for a water nymph. Synonyms such as naiad, nereid, oceanid, and undine are more commonly used to describe these mythological creatures. Naiad refers to a water nymph residing in streams, fountains, and other freshwaters. Nereids live in the Mediterranean Sea and are associated with the god of the sea, Poseidon. Oceanids are water nymphs who were born to the Greek god, Oceanus, and the Titaness, Tethys. Lastly, undines are legendary water spirits found in various bodies of water. These water nymphs play a significant role in Greek mythology, and their beauty and charm have been portrayed in art, literature, and music.