The Japanese oyster, or Crassostrea gigas, is a popular seafood delicacy that is enjoyed around the world. However, many people may not be aware that there are several other synonyms for this delicious mollusk. Some of the commonly used names for the Japanese oyster include the Pacific oyster, Miyagi oyster, and Gigas oyster. Other names that are occasionally used are the Rock oyster, Portuguese oyster, and Galway oyster. Regardless of the name that is used, the Japanese oyster is famous for its sweet, briny flavor and its large size, making it a favorite of many seafood lovers.