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to decide; to determine
to establish; to lay down; to prescribe; to provide; to stipulate
to bring peace (to); to make peaceful
自分の役割を定めた。
I decided on my own role.
法律で安全基準を明確に定めています。
Standards are established by law.
まず目的を定めることが大切だ。
First, set a clear goal.