Is megacity a word? No. If the word existed at all, it would be megapolis.
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According to the American Merriam-Webster Dictionary, the hypenated word mega-city came into (American) usage in 1967 as an alternative for megapolis. The suffix mega- means large and is derived from the Greek megas meaning great. The element -city is of course from Latin, which makes mega-city a hybrid monstro-city of pompo-city to be avoided by all careful speakers. Furthermore, it must be said that Merriam-Webster is not all that highly regarded a name among those who really love this stuff.
The root word of megalopolis is "megas," which comes from Greek and means "great" or "large."
megalopolises
The root word of "unusual" is "usual."
The root word is gift.
The root word of "endless" is "end."
Tri is the root word of intricate. The root word means three.
Megaphone, megacycle, and megalopolis.
megacycle, megalopolis, megabyte, megastar, megalomania, megapixel, megaplex, megaspore, megawatt
City, metropolis, megalopolis
Megalopolis and metropolis are both correct words.
Conurbation!(or any word that would mean large town, city, etc...)
Battle of Megalopolis happened in -331.
An example of a megalopolis can be found in the Northeastern United States where cities like Boston, New York City, Philadelphia, Baltimore, and Washington D.C. form one continuous urban region.
Fugitive has no root word it is the root word.
There is no root word of river. It itself is a root word.
Great Lakes Megalopolis's population is 54,000,000.
Megalopolis Expressway Trial was created in 1992.
"polis" isn't a Greek word, but πόλη (poli) is. That word means "city". Whenever you see "polis" in the name of something it means "city". So, Metropolis means "mother city", Megalopolis means "Great City", and Acropolis means "highest city". The word "politics" comes from the same root.