A developed or advanced country—one with a high level of industrialization, technology, and living standards.
先進国は環境問題への対策を強化している。
Developed countries are strengthening measures against environmental problems.
先進国の多くは高齢化社会に直面している。
Many developed countries are facing an aging society.
先進国と発展途上国の経済格差が話し合われた。
The economic gap between developed and developing countries was discussed.