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.
megalopolises
Root word is usual.
The root word is gift.
end is the root word
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.
Fugitive has no root word it is the root word.
There is no root word of river. It itself is a root word.
megalopolises
the root word is'confirminglyishness'
Root word is usual.
the root word is decor and that is the root word of decorate