noun - Poseidon or Posidon (Greek: Ποσειδῶν) is the ancient Greek god of the sea, with the power to cause earthquakes. Poseidon's Roman counterpart is Neptune, the god of the sea and of earthquakes; brother of Zeus, Hades, and Hera, generally depicted in art wielding a Trident.
Poseidon is one of the twelve Olympian deities of the pantheon in Greek mythology. His main domain is the ocean, called the God of the Sea. Additionally, he is referred to as "Earth-Shaker" due to his role in causing earthquakes, and has been called the "tamer of horses".