estuary

American  

[es-choo-er-ee] / ˈɛs tʃuˌɛr i /

noun

• estuaries
  plural

1. that part of the mouth or lower course of a river in which the river's current meets the sea's tide.

2. an arm or inlet of the sea at the lower end of a river.

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estuary British  

/ ˌɛstjʊˈɛərɪəl, ˈɛstjʊərɪ /

noun

1. the widening channel of a river where it nears the sea, with a mixing of fresh water and salt (tidal) water

2. an inlet of the sea

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estuary Scientific  

/ ĕs′cho̅o̅-ĕr′ē /

1. The wide lower course of a river where it flows into the sea. Estuaries experience tidal flows and their water is a changing mixture of fresh and salt.

2. An arm of the sea that extends inland to meet the mouth of a river.

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estuary Cultural  

1. A wide body of water formed where a large river meets the sea. It contains both fresh and salt water.

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Other Word Forms

Derived Forms

• estuarial
  adjective

Inflected Forms

Nouns

• estuaries
  plural

Etymology

Origin of estuary

First recorded in 1530–40; from Latin aestuārium “channel, creek, inlet,” from aestu(s) “fire, heat, tide” + -ārium -ary

Explanation

An estuary is the place in the water where a tide and a river current meet, like the estuary at New York Harbor, where the Hudson River meets the Atlantic Ocean. Estuary, pronounced "ES-choo-air-ee," comes from the Latin word aestuarium, meaning "a tidal marsh or opening." The calm waters of an estuary, where the mouth of a river connects with the open sea and fresh water mixes with salty ocean water, makes the perfect home for many species of aquatic plants and animals. Chesapeake Bay and Puget Sound are estuaries.

Example Sentences

See Examples For:

estuary estuaries

Then we paddled around the estuary on a pre-breakfast kayak tour.

From Los Angeles Times ● Aug. 13, 2026

Friends of the River Teign, external is one such group uses volunteers equipped with real-time testing kits to provide "more frequent, more localised water quality information across River Teign estuary and surrounding coastal waters".

From BBC ● Aug. 1, 2026

In Foynes village across the estuary from the refinery, where a port handles its exports, local businessman John Cassels said the dilemma was clear.

From Barron's ● Jul. 24, 2026

Along river mouths, this distance is extended to 500 metres with respect to the estuary.

From Science Daily ● May 21, 2026

That river, that chalk quarry, that estuary in the glimmering night—familiar landmarks.

From "Code Name Verity" by Elizabeth Wein

They placed groups of these tiles in three estuaries in the Sydney region, Brisbane Water, the Hawkesbury River and Port Hacking, near existing oyster reefs where larvae are present.

From Science Daily ● Apr. 6, 2026

The Florida Everglades are a unique environmental region comprising marshes, prairies, forests, mangroves and estuaries.

From BBC ● Jun. 23, 2025

There are also concerns for the survival of migratory birds, many of which make stop-offs on Britain’s vast shorelines and estuaries.

From BBC ● Oct. 28, 2024

And farmed shellfish, which can help restore oceans, estuaries, or our coastlines.

From Salon ● Sep. 23, 2024

This has to do with the fishes of salt marshes, bays, and estuaries.

From "Silent Spring" by Rachel Carson

Related Words

• inlet
• waterway