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selfishness; egotism; egoism; (being) self-centered; without consulting; (doing) as one pleases; one's own free will
そんな自分勝手は許されない。
Such selfishness is not acceptable.
自分勝手な行動が周囲を困らせた。
Self-centered behavior troubled those around him.
チームで働くには自分勝手をやめることが大切だ。
To work in a team, stop acting selfishly.