Lagoon

Lagoon

/lə-ˈgün/

Noun

a shallow body of water, especially one separated from the sea by sandbars or coral reefs

“There are two types of lagoons: atoll and coastal. Atoll lagoons form when an island completely subsides beneath the water, leaving a ring of coral that continues to grow upwards… Coastal lagoons form along gently sloping coasts. They are generally shallower than atoll lagoons and tend to be separated from the ocean by an island, reef, or sand bank.”

– National Oceanic and Atmospheric Administration (NOAA)