Q. Does “Yom Kippur” literally translate as “Day of Atonement”?
A. No. The English verb “atone” was originally two words, “at” and “one”, and atonement thus denotes reconciliation. Kippur, however, comes from a root that probably means to cover or hide; a secondary meaning is to obliterate (sin) and hence to expiate.
An interesting question is whether there is a link with kapporet, usually translated “mercy seat” or “ark covering”.
The phrase “mercy seat” was introduced in Tyndale’s translation of the Bible, influenced by Martin Luther, who used the word “Gnadenstuhl”. This is a highly unlikely to be correct, but nor does kapporet merely indicate a physical lid for the ark of the covenant.
A better view is that of Ibn Ezra, that the word indicates the task and not just the shape of the ark cover. Since the blood of the Yom Kippur sacrifice was sprinkled in its direction (Lev. 16), it was the symbol of propitiation. This is probably why the Holy of Holies itself is called bet hakapporet, “the place of propitiation” (I Chron. 28:11).
So Yom Kippur and the kapporet have a common origin.