The English word atonement etymologically means at-one-ment.

Evidence

In English, the word “atonement” captures some of this in the sense that it can be understood as “at-one-ment.” Yom Kippur, of course, is known as the “Day of Atonement.” — Martin Jay, The Dialectical Imagination, 1565

Categorization

• CANDY: A lightweight etymology nugget — ‘atonement’ as ‘at-one-ment’ — nice elevator trivia.