What Are the Differences Between an Ocean, a Sea, a Bay and a Gulf?

By Staff WriterLast Updated Apr 12, 2020 9:34:00 PM ET
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Oceans, seas, bays and gulfs are all primarily distinguished by size. An ocean and a sea differ mainly by size as oceans are larger than seas. Similarly, the difference between a bay and a gulf is also based on size. Gulfs are larger than bays, and small bays are sometimes called coves.