Webster's Revised Unabridged Dictionary · 1913

lagoon

lagoon (lȧ*gon") , noun

[Italian or Sp. laguna, Latin lacuna ditch, pool, pond, lacus lake. See Lake, and compare Lacuna.]

1.
A shallow sound, channel, pond, or lake, especially one into which the sea flows; as, the lagoons of Venice.
2.
A lake in a coral island, often occupying a large portion of its area, and usually communicating with the sea. See Atoll.
Collocations (1)
Lagoon island , a coral island consisting of a narrow reef encircling a lagoon.