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integrity; moral courage; rigidity
剛直な性格で上司にも臆せず意見を言う。
With his upright character, he speaks his mind to superiors without hesitation.
剛直な武士が不正を許さず立ち上がった。
An upright warrior rose up, refusing to tolerate injustice.
彼の剛直さは敵にも尊敬されていた。
His moral courage was respected even by his enemies.