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envoy; diplomat below the rank of ambassador (e.g. deputy chief of mission, charge d'affaires); minister (of legation)
公使が相手国の首脳と会談を行った。
The envoy held talks with the counterpart country's leader.
新任の公使が赴任先に到着した。
The newly appointed envoy arrived at his post.
公使として外交交渉の最前線に立つ。
As an envoy, one stands at the forefront of diplomatic negotiations.