RheafGreek Mythology, Roman Mythology Meaning unknown, perhaps related to ῥέω (rheo) meaning "to flow" or ἔρα (era) meaning "ground". In Greek mythology Rhea was a Titan, the wife of Cronus, and the mother of the Olympian gods Zeus, Poseidon, Hades, Hera, Demeter and Hestia. Also, in Roman mythology a woman named Rhea Silvia was the mother of Romulus and Remus, the legendary founders of Rome.