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head; leader; top
各国の主脳が集まり国際会議が開催された。
Leaders from various countries gathered and an international conference was held.
主脳会談で両国間の貿易協定が締結された。
A trade agreement between the two countries was concluded at the summit.
組織の主脳として重大な決断を下す立場にある。
As the head of the organization, one is in a position to make critical decisions.