Revenge

1. harm

1.1. Physical injury,especially that which is deliberately inflicted.

1.2. Its fine as long as no one is inflicting harm on anyone else.

2. satisfaction

2.1. fulfillment of one's wishes or expectations

2.2. contentment

2.3. he smiled with satisfaction

3. retribution

3.1. punishment inflicted on someone

3.2. Example, He decided to back down,in fear of violent retribution.

4. pay back

4.1. An act of revenge or retaliation

4.2. School loan consolidation can make payback easier, but it isn't without pitfalls.