* Μητρόπολη (Mitrópoli): This translates literally to "mother city" and often refers to a principal city, a capital or a historically significant city from which others stemmed. It implies importance and influence, but not necessarily current dominance.
* Πρωτεύουσα (Protoyeousa): This means "capital city," indicating the primary city of a region or country. This is a good option if "top" refers to political importance.
* Μεγάλη πόλη (Megali poli): This simply means "big city" or "great city." It's a descriptive term, focusing on size and importance, but not necessarily implying it's the *most* important.
The best choice depends heavily on the context. To choose the most appropriate word, consider what makes the city "top" – is it its size, political significance, historical importance, economic power, or something else?