A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a gulf, sea, sound, or bight. A cove is a small, circular bay with a narrow entrance. A fjord is an elongated bay formed by glacial action.
The term embayment is also used for related features, such as extinct bays or freshwater environments.
A bay can be the estuary of a river, such as the Chesapeake Bay, an estuary of the Susquehanna River. Bays may also be nested within each other; for example, James Bay is an arm of Hudson Bay in northeastern Canada. Some large bays, such as the Bay of Bengal and Hudson Bay, have varied marine geology.
The land surrounding a bay often reduces the strength of winds and blocks waves. Bays may have as wide a variety of shoreline characteristics as other shorelines. From Wikipedia
