lagoon \la*goon"\ (l[.a]*g[=oo]n"), n. [It. or Sp. laguna, L.
   lacuna ditch, pool, pond, lacus lake. See Lake, and cf.
   Lacuna.] [Written also lagune.]
   1. A shallow sound, channel, pond, or lake, especially one
      into which the sea flows; as, the lagoons of Venice.
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   2. A lake in a coral island, often occupying a large portion
      of its area, and usually communicating with the sea. See
      Atoll.
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   Lagoon island, a coral island consisting of a narrow reef
      encircling a lagoon.
      [1913 Webster] Lagophthalmia