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to refuse; to reject; to turn down; to dismiss
to repel; to repulse; to drive away; to beat off; to defeat
to make (someone) leave; to send away; to turn away
to force (someone) to leave their post; to oust; to remove; to expel
「退ける」 has other readings with different meanings.
反対意見を退けて計画を強引に進めた。
We pushed forward with the plan, rejecting opposing opinions.
敵の攻撃を勇敢に退けることができた。
We were able to bravely repel the enemy's attack.
彼は強い意志で目の前の誘惑を退けた。
He rejected temptation with strong will.