Monergism

Atonement is the term that has come to be widely used to denote the substitutionary work of Christ which culminated in the sacrifice of Calvary. The term occurs frequently in the A.V. of the Old Testament as the rendering of the Hebrew root kaphar but only once in the New Testament (Rom. 5:11) where it refers to the reconciliation. The term itself is not adequate to express what is involved in Christ's vicarious work. In fact, no one term can express the manifold aspects from which, according to Scripture, this work of Christ must be viewed. Atonement, however, when understood in the way that usage has determined, is sufficiently inclusive to serve as a general designation.
John Murray