meg·​a·​lop·​o·​lis | \ ˌme-gə-ˈlä-pə-ləs \

Definition of megalopolis 

1 : a very large city
2 : a thickly populated region centering in a metropolis or embracing several metropolises

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Other Words from megalopolis

megalopolitan \ -​lō-​ˈpä-​lə-​tən \ noun or adjective

Did You Know?

A "large city" named Megalopolis was founded in Greece in 371 B.C. to help defend the region called Arcadia against the city-state of Sparta. Though a stadium seating 20,000 was built there, indicating the city's impressive size for its time, Megalopolis today has only about 5,000 people. Social scientists now identify 10 megalopolises in the U.S., each with more than 10 million people. The one on the eastern seaboard that stretches from Boston to Washington, D.C., where the densely populated cities seem to flow into each other all along the coast, is now home to over 50 million people. But it's easily surpassed by the Japanese megalopolis that includes Tokyo, with more than 80 million inhabitants.

Examples of megalopolis in a Sentence

what was once a series of discrete towns interspersed with countryside is now one vast megalopolis

Recent Examples on the Web

Rick, how much will this storm affect the megalopolis, from Boston, New York, Philadelphia, D.C., Richmond? Fox News, "Nation marks 17 years since attacks of Sept. 11," 12 Sep. 2018 But as the megalopolis grew, the zoo became surrounded by an urban sprawl of busy avenues with honking buses and screeching cars near the animal enclosures, where on a recent day a solitary lion spent his time chasing his tail in circles. Luis Andres Henao, Fox News, "Giraffe, rhino deaths raise alarm at former Buenos Aires zoo," 22 Aug. 2018 Though Wagner was wrong to predict that Vienna would become such a city, his thinking about infinite urban expansion can easily be applied to megalopolises in modern-day Asia. A. J. Goldmann, WSJ, "How Otto Wagner Made Vienna Modern," 12 June 2018 Many Vermonters have mobilized to oppose his vision of a megalopolis of 1 million people, nearly twice the state’s current population. Brian Macquarrie,, "Preservation group places small Vermont towns on ‘watch status’," 26 June 2018 Finally, modern technology allows cities to reach megalopolis sizes by our day. Andrew Moseman, Popular Mechanics, "One GIF Shows How the World's Biggest City Shifted Throughout History," 22 Dec. 2016 But many structures that surrounded the ruins remained hidden beneath the dense colonial city—and now, the modern megalopolis. Lizzie Wade, Science | AAAS, "Feeding the gods: Hundreds of skulls reveal massive scale of human sacrifice in Aztec capital," 21 June 2018 In the Northeastern megalopolis, Pennsylvania has nine cases, neighboring New Jersey has seven, New York and Connecticut have two each. David J. Neal, miamiherald, "Here's the cause of the E. coli outbreak, along with a warning from the CDC and FDA | Miami Herald," 13 Apr. 2018 But on Wednesday, Mayor Miguel Angel Mancera said some group has been shutting off water distribution valves at about 50 points in the sprawling megalopolis. Fox News, "Mexico City: Water cutoffs in capital worsened by sabotage," 7 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'megalopolis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of megalopolis

circa 1828, in the meaning defined at sense 1

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Last Updated

26 Dec 2018

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Time Traveler for megalopolis

The first known use of megalopolis was circa 1828

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English Language Learners Definition of megalopolis

: a very large city

: an area that includes a large city or several large cities

More from Merriam-Webster on megalopolis

Thesaurus: All synonyms and antonyms for megalopolis Encyclopedia article about megalopolis

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