Estuary

Definition of estuary: A semi-enclosed littoral basin (embayment) of the coast in which fresh river water entering at its head mixes with saline water entering from the ocean. Fully developed estuarine systems consist of complex dynamic interactions between channels, tidal flats, middle ground shoals and salt marshes. Estuaries are of particular ecological value and significance because they provide important natural values concerning, for example, fish and wildlife habitat, flood protection, and maintenance of water quality. This is the common definition for estuary, other definitions can be discussed in the article