Propitiation is an action meant to regain someone's favor or make up for something you did wrong. You might offer your mom a plate of chocolate chip cookies in propitiation for killing all her houseplants while she was away.
Propitiation comes from a form of the Latin verb "propitiare," which means “to appease.” If you’re doing something in propitiation, that’s your basic goal: to regain favor. Propitiation often involves a god or gods, traditional or not. If your team lost last year's championship, propitiation of the football gods may be necessary this year. More broadly you can offer propitiation to anyone you need to appease. Propitiation may be needed if you show up late to class again.