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haughty; arrogant; insolent; presumptuous
不遜な態度が上司の怒りを買った。
His arrogant attitude incurred his boss's anger.
若者の不遜な発言に会場が静まり返った。
The young person's insolent remarks silenced the venue.
才能があっても不遜であれば人は離れていく。
Even with talent, if you are arrogant, people will distance themselves.