The question of determining the world's largest cities does not allow a single, simple answer. It depends on which definitions of "city" and "size" are used, and how those definitions are applied. Complex political/cultural/social situations, sometimes controversial or disputed, further confuse the discussion. Debate on this field is highly vulnerable to bias or manipulation, as people tend to prefer whichever definition most flatters their own city.

The "size" of a city can refer to either its land area or, more typically, its population.

The borders of a city can also be defined in any of several ways:

Morphological
"City" defined as a physically contiguous urban area, without regard to territorial or other boundaries. The delineation is usually done using some type of urban density, such as population density or density of buildings (for example, "gaps between structures may not exceed 200 metres"). Satellite and/or aerial maps may be used. For statistical convenience, such areas are sometimes adjusted to appropriate administrative boundaries, yielding an agglomeration.
Main articles: List of urban areas by population and List of urban agglomerations by population (United Nations)
Functional
"City" as defined by the habits of its demographic population, as by metropolitan area, labor market area, or similar. Such definitions are usually based on commuting between home and work. Commuter flow thresholds into the core urban area are established by the national census authority, determining which areas are included.
Main article: List of metropolitan areas by population
Administrative
"City" as strictly defined by a given government (city proper). Typically based on a municipality or equivalent entity, or sometimes a group of municipalities under a regional government.
Main articles: List of cities proper by population and List of cities by surface area

From Wikipedia under the GNU Free Documentation License
Fri Sep 3 14:16:59 2010

What is the largest city between Montreal and Toronto in Ontario?
Q. Between Montreal and Toronto, anyone know the largest city?
Asked by Brandon R - Wed Feb 4 19:18:06 2009 - - 6 Answers - 0 Comments

A. The largest city between Toronto and Montreal is Ottawa. Ottawa has a metropolitan population estimated at 1,190,982 making it the 4th largest municipality in Canada. Detailed below is the 5 largest municipalities in terms of population: Toronto = 5,113,149 (CMA); 5,555,912 (GTA) Montreal = 3,635,571 (CMA) Vancouver = 2,285,900 (CMA) Ottawa = 1,190,982 (CMA) Calgary = 1,162,310 (CMA)
Answered by Patrick - Wed Feb 4 19:34:04 2009

What is the largest city between denver and the west coast?
Q. What is the largest city between denver and the west coast?
Asked by just me :]]] - Sun Mar 2 21:53:34 2008 - - 3 Answers - 1 Comments

A. Phoenix, AZ
Answered by Max - Sun Mar 2 22:12:57 2008

What is the largest city in the world, according to population?
Q. What is the largest city in the world, according to population?
Asked by ryan_41014 - Mon May 21 16:30:01 2007 - - 9 Answers - 0 Comments

A. Tokyo or Mexico City
Answered by boxjelly - Mon May 21 16:38:07 2007

From Yahoo Answer Search: "largest city"
Fri Sep 3 14:17:00 2010

Discover the Charms of Sumptuous Sevilla - Rundtownnews.co.uk
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Discover the Charms of Sumptuous Sevilla

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And from your central hotel, it is made so very easy for you to discover this intoxicating capital that is Spain's 4th largest city . ...
The Elizabethan era we didn't know - News & Observer
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The Elizabethan era we didn't know

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Unlike Cauble, White will be based in Raleigh, which was described as an effort to strengthen relations between Raleigh and the state's largest city . ...



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A different kind of parking ticket - OregonLive.com (blog)
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A different kind of parking ticket

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The parked vehicles were airplanes, not cars. And it happened in the middle of Minnesota's largest city . Actually, that sort makes things stranger, doesn't it?



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From Google News Search: "largest city"
Fri Sep 3 14:17:00 2010

Deltona mayor Dennis Mulder outlined a proposal to reduce or do
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Deltona mayor Dennis Mulder outlined a proposal to reduce or do
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A boy covered in mud sits on the floor of a church in Gonaives
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From Yahoo Image Search: "largest city"
Fri Sep 3 14:17:00 2010

Mesa Arizona Homes For Sale | Equipment and Construction News
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Mesa Arizona Homes For Sale | Equipment and Construction News

Sharlene Webb

Fri, 23 Jul 2010 08:03:06 GM

Over the last several decades, there has been a population shift among the . largest cities. in the nation, especially those that border Mexico. The fifth . largest city. in the country, with a population of 1.5 million as of 2006, ...

- seanswire's blog
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- seanswire's blog

seanswire

Fri, 23 Jul 2010 18:52:11 GM

Dallas, Texas is a Great Place to Live: Image : Dallas, Texas is the third . largest city. f...

 City of Ephesus
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City of Ephesus

unknown

Wed, 21 Jul 2010 06:19:48 GM

In the first century, when St. Paul came, there were about a million people living in Ephesus and it was the second . largest city. in the Roman Empire after Rome itself. It was here that St. Paul was driven out of town by the silversmiths ...

From Google Blog Search: "largest city"
Fri Sep 3 14:17:00 2010