What is an acknowledgment intended as an atonement for some improper or injurious remark or act; an admission to another of a wrong or discourtesy done him, accompanied by an expression of regret called?

apology — An acknowledgment intended as an atonement for some improper or injurious remark or act; an admission to another of a wrong or discourtesy done him, accompanied by an expression of regret. (Webster's 1913.)

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