Lagoon

noun (countable)

/ləˈɡuːn/

A shallow body of water separated from the open sea by a low-lying barrier such as a coral reef, sandspit, or barrier island, with limited or seasonal connection to the ocean through inlets or tidal channels. Coastal lagoons are highly productive ecosystems. In India, Chilika Lake in Odisha is a brackish-water lagoon and a Ramsar site (designated 1 October 1981); Pulicat Lake on the Andhra Pradesh–Tamil Nadu border is another major example.

✍️ Usage in a UPSC answer

Chilika Lake, a brackish-water lagoon and a Ramsar site since 1 October 1981, is a breeding, wintering and staging area for 33 species of waterbirds and supports 118 species of fish (Ramsar site sheet).

Synonyms

coastal lakebrackish lakeatoll lakeback-barrier lakeestuary (partial)tidal flat

Antonyms

open seadeep oceanfluvial laketectonic lakecrater lake

🌱 Word Family

lagoon (noun), lagoonal (adjective), lagoonal deposit (compound noun), laguna (Spanish variant)

🔡 Root

Italian laguna = pool, pond; from Latin lacuna = pit, hole, pool; from lacus = lake

📜 Etymology

Borrowed from Italian laguna (shallow lake or pool), which derives from Latin lacuna (a pit, ditch, or pool), itself from lacus (lake). The word is now applied to any shallow coastal water body separated from the sea. The English variant lagune also circulated before the modern spelling stabilised.

🧠 Memory Hook

LAGOON = a LAKE GONe saltwater-y. A lagoon is a lake-like body trapped behind a coastal barrier, mixing freshwater with sea. Venice sits in one; imagine gondolas gliding in a partially enclosed 'lake'.

📝 Seen in UPSC Question Papers

Prelims 2025 — World Geography
Prelims 2025 — World Geography

Real UPSC previous-year questions whose text uses “Lagoon” — proof this word earns its place on your list.

🌍 Geography 📖 Seen in: Plate Tectonics and Volcanism…

Relevant across:GS1 · History, Geography & Society

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