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impudence; audacity; shamelessness; effrontery
厚顔無恥な態度に周囲が呆れ返った。
Everyone was utterly appalled by his shameless attitude.
厚顔にも自分の手柄だと主張した。
He shamelessly claimed it as his own achievement.
これほど厚顔な人物は見たことがない。
I have never seen such an impudent person.