estuary
Americannoun
plural
estuaries-
that part of the mouth or lower course of a river in which the river's current meets the sea's tide.
-
an arm or inlet of the sea at the lower end of a river.
noun
-
the widening channel of a river where it nears the sea, with a mixing of fresh water and salt (tidal) water
-
an inlet of the sea
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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.
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An arm of the sea that extends inland to meet the mouth of a river.
Other Word Forms
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.
Vocabulary lists containing estuary
Physical Geography - Introductory
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Seas The Day: Words That Shore Are Beachy
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Physical Geography - Middle School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Much of the uncaptured Mexican waste flows into the Tijuana River, which crosses a U.S. estuary before reaching the Pacific.
From The Wall Street Journal • May 4, 2026
The environment 132 million years ago would have looked very different from today's coastline, estuary, and developed landscape.
From Science Daily • Apr. 24, 2026
The tidal Scheldt river estuary is the main maritime access route to Antwerp port, along with several narrower canals primarily used for inland navigation.
From Barron's • Apr. 10, 2026
Through the estuary window, they see a planet in peril.
From Los Angeles Times • Feb. 14, 2026
Immediately he started talking about the Volta estuary.
From "Flying Through Water" by Mamle Wolo
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
