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.

---

estuary British  

/ 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

---

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.

---

estuary Cultural  

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

---

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

Around river mouths, the distance extends to 500 meters from the estuary.

From Science Daily ● Sep. 10, 2026

During the Second World War, he became a member of the Home Guard and patrolled Conwy estuary in the event of an enemy invasion.

From BBC ● Sep. 10, 2026

Once adopted, the state plan will set rules that determine how much water can be pumped out of the Delta and how much should stay in rivers and the estuary for fish and the environment.

From Los Angeles Times ● Sep. 9, 2026

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

From Los Angeles Times ● Aug. 13, 2026

They rowed the length of the estuary and out along the mudflats on the east shore of the bay.

From "The Boys in the Boat: Nine Americans and Their Epic Quest for Gold at the 1936 Berlin Olympics" by Daniel James Brown

The researchers examined more than 2,580 MHWs recorded across 20 U.S. estuaries over two decades.

From Science Daily ● Sep. 30, 2026

Using long term observations from 20 U.S. estuaries, the researchers developed a way to measure total heat exposure by viewing marine heatwaves as part of broader warming episodes rather than as isolated events.

From Science Daily ● Sep. 30, 2026

They are also found around river mouths, estuaries and manmade structures like piers and groynes.

From BBC ● Aug. 23, 2025

Like with rivers, estuaries and areas of the sea around Wales are protected for their important habitats and wildlife.

From BBC ● Jun. 24, 2025

In the entire period of their inshore life, the welfare of the shrimp populations and of the industry they support depends upon favorable conditions in the estuaries.

From "Silent Spring" by Rachel Carson

Random Word

Spin the wheel and learn a new word!

---

Related Words

• inlet
• waterway

---