A bay is a body of water partly surrounded by land and connected to a larger body of water. It is typically bigger than a cove and smaller than a gulf. However, this is not always the case. For example, Hudson Bay is
much larger than the Persian Gulf. Strictly speaking and by international agreement, to be defined as a bay, a water body’s mouth (the boundary between itself and the larger body of water to which it is connected) must not exceed 24 nautical miles. In
addition, its area must exceed that of a semicircle drawn with the mouth as its diameter.