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large country; major nation; great power
province of the highest rank (ritsuryō system)
大国間の協力が世界平和に不可欠だ。
Cooperation between major powers is essential for world peace.
経済大国としての責任が問われている。
Its responsibility as an economic power is being questioned.
大国の政策変更は周辺国に大きな影響を与える。
Policy changes by a major power greatly affect neighboring countries.