estuary

noun

es·​tu·​ary ˈes-chə-ˌwer-ē How to pronounce estuary (audio)
ˈesh-
plural estuaries
: a water passage where the tide meets a river current
especially : an arm of the sea at the lower end of a river

Did you know?

A partly enclosed coastal body of water in which river water is mixed with seawater is called an estuary. An estuary is thus defined by salinity rather than geography. Many coastal features designated by other names are in fact estuaries (for instance, Chesapeake Bay). Some of the oldest continuous civilizations have flourished in estuarine environments (for example, the Tigris and Euphrates rivers, the Nile delta, and the Ganges delta). Cities such as London (Thames River), New York (Hudson River), and Montreal (St. Lawrence River) developed on estuaries and became important commercial centers.

Examples of estuary in a Sentence

the city sits on the shores of a deep estuary where the Hudson River meets the Atlantic Ocean
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
According to Eustis the spill threatens a range of species including black terns, bottlenose dolphins, larval yellowfin tuna, marsh birds, spring pogies, and young fish migrating into the estuaries for spring growth. Dan Ruetenik, CBS News, 2 May 2025 Currently, more than 8,000 people live in flood plain areas along estuaries in the Cascadia coastal region. Rong-Gong Lin Ii, Los Angeles Times, 30 Apr. 2025 The team found that if an earthquake that caused more than six feet of subsidence were to happen today, the 100-year floodplain in estuaries in Cascadia would expand by 115 square miles. Stephanie Pappas, Scientific American, 30 Apr. 2025 But, to their delight, the whale was last seen on the afternoon of March 25, appearing to exit the estuary. Brendan Rascius, Miami Herald, 28 Mar. 2025 See All Example Sentences for estuary

Word History

Etymology

Latin aestuarium, from aestus boiling, tide; akin to Latin aestas summer — more at edify

First Known Use

1538, in the meaning defined above

Time Traveler
The first known use of estuary was in 1538

Browse Nearby Words

Cite this Entry

“Estuary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/estuary. Accessed 6 May. 2025.

Kids Definition

estuary

noun
es·​tu·​ary ˈes-chə-ˌwer-ē How to pronounce estuary (audio)
plural estuaries
: a passage where the tide meets a river current
especially : an arm of the sea at the lower end of a river
estuarine
ˈes-chə-wə-ˌrīn
adjective

More from Merriam-Webster on estuary

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