Scapegoat

The scapegoat apparently was a goat that was driven off into the wilderness as part of the ceremonies of Yom Kippur, the Day of Atonement, in Judaism. The rite is described in Leviticus 16. Two male goats were to be brought to the place of sacrifice along with a bull. The high priest then cast lots for the two goats. One goat was offered as a burnt offering, as was the bull. The second goat was the scapegoat. The high priest placed his hands on the head of the goat and confessed the sins of the people of Israel. The goat was then led away into the wilderness, bearing the sins of the people with it, to be claimed by the fallen angel Azazel.

Figuratively, a scapegoat is someone selected arbitrarily to bear blame for a calamity. See scapegoating