A very large city or metropolis. Characterized by concentrated population and buildings; can imply bustling, convenient, but hectic urban life.
田舎から大都会に出てきて、生活に慣れるのに時間がかかった。
I moved from the countryside to the big city and it took time to get used to life there.
大都会の交通は便利だが、通勤ラッシュが厳しい。
Public transportation in the metropolis is convenient, but the commuting rush is severe.
大都会の夜景はとても美しい。
The night view of the metropolis is very beautiful.