expiator
/ˌɛksˈpɪeɪtər/Definitions
1. noun
A person or thing that makes amends or atones for something
“The charity served as an expiator for the company’s past environmental mistakes.”
2. noun
A person who performs a ritual or sacrifice to atone for a sin or offense
“In ancient cultures, the priest played the role of the expiator, offering sacrifices to appease the gods.”