Exodus 30:10וְכִפֶּר
Once a year Aaron shall make atonement on the horns of the altar. Throughout your generations he shall make atonement on it annually with the blood of the sin offering of atonement. The altar is most holy to the LORD.”
Leviticus 1:4לְכַפֵּר
He is to lay his hand on the head of the burnt offering, so it can be accepted on his behalf to make atonement for him.
Numbers 5:8יְכַפֶּר
But if the man has no relative to whom restitution can be made for the wrong, the restitution belongs to the LORD and must be given to the priest along with the ram of atonement, by which the atonement is made for him.
Deuteronomy 21:8כַּפֵּר
Accept this atonement, O LORD, for Your people Israel whom You have redeemed, and do not hold the shedding of innocent blood against them.” And the bloodshed will be atoned for.
Isaiah 6:7תְּכֻפָּר
And with it he touched my mouth and said: “Now that this has touched your lips, your iniquity is removed and your sin is atoned for.”
Ezekiel 16:63בְּכַפְּרִי
so that when I make atonement for all you have done, you will remember and be ashamed and never again open your mouth because of your disgrace, declares the Lord GOD.”

Brown-Driver-Briggs

כִּפֶּר vb. Pi. etc. denom. cover over (fig.), pacify, make propitiation

Pi.

1. cover over, pacify, propitiate

2. cover over, atone for sin, without sacrifice

3. cover over, atone for sin and persons by legal rites

Pu. be covered over, atoned for

Hithp. the iniquity of the house of Eli shall not be covered by peace-offering or minchah

Niph. and the blood shall be covered for them

Sources: Brown-Driver-Briggs (1906, public domain) from the Open Scriptures Hebrew Lexicon (CC BY 4.0), glosses from STEPBible TBESH (CC BY 4.0); STEPBible TAHOT (Hebrew Bible, Leningrad Codex, CC BY 4.0); the Berean Standard Bible (public domain). Reformatted by Word Study, wording unchanged. All sources and licenses.