Marmara, Sea of Syllabification: (Mar·ma·ra, Sea of)Pronunciation: /ˈmärmərə/Definition of Marmara, Sea of a small sea in northwestern Turkey. Connected by the Bosporus to the Black Sea and by the Dardanelles to the Aegean Sea, it separates European Turkey from Asian Turkey. In ancient times it was known as the Propontis. Marmara, Sea of in other Oxford dictionaries Definition of Marmara, Sea of in the British & World English dictionary