The definition of a megalopolis is a large and densely populated city or group of towns that make up an urban complex.(noun)
New York City and surrounding areas including Long Island are an example of a megalopolis.
See megalopolis in Webster's New World College Dictionary
Origin: Gr, lit., great city
See megalopolis in American Heritage Dictionary 4
Origin: + Greek polis, city; see pelə-3 in Indo-European roots.
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