sphere of influence

Noun

The area (literal or figurative) influenced by a country, person, etc.

Japanese Meaning

影響圏 / 勢力範囲 / 影響下の領域

During the Cold War, both superpowers expanded their sphere of influence through alliances and proxy conflicts.

冷戦期間中、両超大国は同盟や代理紛争を通じて勢力圏を拡大した。

Sense（1）

The area (literal or figurative) influenced by a country, person, etc.

spheres of influence

（ plural ）