megacity

megacity — noun

1. A city that has an extremely large number of residents, typically ten million or

1.nounB2
Definition

A city that has an extremely large number of residents, typically ten million or more, creating major challenges for housing, transport, and other services.

Example

Tokyo is a megacity with over thirty-seven million people in its wider metro area.

be + a megacity — classifying a city

The megacity of Mumbai has a train system that carries millions daily.

the megacity of [place name]

Common collocations
  • grow into a megacity
  • become a megacity
  • megacity population
  • megacity infrastructure
  • live in a megacity
  • megacity dweller
Synonyms
  • metropolis

    A broad term for any large, important city; does not specify a population threshold and can refer to cities smaller than ten million.

  • conurbation

    A technical term for a continuous urban area formed when separate towns and cities grow together; may or may not reach megacity population.

  • megalopolis

    An even larger scale — a chain of connected metropolitan regions, such as the Boston–Washington corridor.

Antonyms
  • village

    A small settlement in a rural area, far smaller than a megacity in both population and density.

  • small town

    A community with only a few thousand residents, lacking the scale and complexity of a megacity.

Grammar Patterns

megacity + of + place name

become / grow into + a megacity

Usage Note

Different organizations use slightly different population thresholds; the United Nations defines a megacity as a metropolitan area with more than ten million inhabitants. This term appears most often in geography, demography, and urban-planning discussions.

Common Mistakes

Tokyo is a mega city with 37 million people.
Tokyo is a megacity with 37 million people.
The word is written as one word, not two.
I live in a megacity that called Shanghai.
I live in a megacity called Shanghai.
Use 'called' (past participle) instead of 'that called' to introduce the name.

Word family

Synonym discussion

Sense: noun/1

Megacity, metropolis, conurbation, and megalopolis all describe large urban areas, but they differ in scale and formality. Metropolis is the most general term: it refers to any important, large city and carries no fixed population threshold. Conurbation is a technical term used by geographers for a zone where towns and cities have physically merged into one continuous built-up area; it can describe a region with far fewer than ten million people. Megalopolis sits at the largest end of the scale, describing a chain of several connected metropolises — for instance, the BosWash corridor in the United States. Megacity sits between metropolis and megalopolis: it implies a population of at least ten million within a single metropolitan area, with the density and infrastructure strain that comes with that size. In everyday speech, metropolis is the most natural choice for a big city; megacity is used when the speaker wants to emphasize the extreme scale and the problems it creates.

megacity ↗metropolis ↗conurbationmegalopolis

Common collocations

Nouns

Adverbs

Phrases

  • grow into a megacity
  • reach megacity status
  • megacity of [place name]

Prepositions

  • in a megacity
  • of a megacity
  • to a megacity

Etymology

GreekLatinFrenchEnglish

Megacity combines mega- (from Greek megas, meaning 'great' or 'large') with city (from Latin civitas via Old French cité). The prefix mega- became productive in twentieth-century English for forming words that mean 'extremely large' (megastore, megastar). The compound megacity entered general use in the late 1900s, as urbanization created metropolitan areas whose populations dwarfed anything seen before.