Atonement

[Hanseng]

The word "atonement" appears in the KJV New Testament just one time: 

Ro 5:11  And not only [so], but we also joy in God through our Lord Jesus Christ, by whom we have now received the atonement. 

The Greek word for atonement is καταλλαγή [SN/OLB# 2643] OLB refers to the Online Bible computer program.

2643 is used 4 times in the NT. Except for Romans 5:11, it is translated as reconcile/d or reconciliation:

Ro 11:15  For if the casting away of them [be] the reconciling <2643> of the world, what [shall] the receiving [of them be], but life from the dead?

2Co 5:18  And all things [are] of God, who hath reconciled us to himself by Jesus Christ, and hath given to us the ministry of reconciliation <2643>;

2Co 5:19  To wit, that God was in Christ, reconciling the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation <2643>

A closely related word is καταλλάσσω [2644]:

Ro 5:10  For if, when we were enemies, we were reconciled <2644> to God by the death of his Son, much more, being reconciled <2644>, we shall be saved by his life.
1Co 7:11  But and if she depart, let her remain unmarried, or be reconciled <2644> to [her] husband: and let not the husband put away [his] wife.
2Co 5:18  And all things [are] of God, who hath reconciled <2644> us to himself by Jesus Christ, and hath given to us the ministry of reconciliation;
2Co 5:19  To wit, that God was in Christ, reconciling <2644> the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation.
2Co 5:20  Now then we are ambassadors for Christ, as though God did beseech [you] by us: we pray [you] in Christ’s stead, be ye reconciled <2644> to God.

 Sometimes the Greek words numbered 2643, a verb, and 2644, a noun, appear in the same verse The translation term, "atonement", used in Romans 5:11 is an outlier in  the KJV.

The Day of Atonement service in Leviticus 16 is explained in  Hebrews 10. The word "atonement" is not mentioned

1 Corinthians 7:11 uses the word translated as "atonement" in Romans 5.11. It refers to the reconciling of a couple in a troubled marriage.   

[Hanseng]

Ro 5:10  For if when we were enemies we were reconciled to God through the death of His Son, much more, having been reconciled, we shall be saved by His life.

2Co 5:19  that is, that God was in Christ reconciling the world to Himself, not imputing their trespasses to them, and has committed to us the word of reconciliation.

The word "imputing" is also translated as "counted" and "reckon." Same word used in describing Abraham, "It was counted to him for righteousness."

God does not count sin against us because Jesus died for us.