If you avenge a wrong or harmful act, you hurt or punish the person who did it. Avenge is always a verb. You avenge a person who has been killed, avenge a murder, or avenge yourself.

1. When a man was killed, it was his family’s duty to avenge him.
2. He muttered time and time again that he would avenge his father’s death.
3. … a cold blooded desire to avenge himself on all humanity.

If someone takes revenge, or does something in revenge, they hurt someone because that person has hurt them or someone they care about. Revenge is usually a noun.

4. What if Stein took revenge upon Breslow’s daughter?
5. He will be safe from the dead man’s relative who seeks revenge.
6. I suppose a more sensual woman would have taken a lover in revenge.

Revenge is occasionally used as a verb. If you revenge yourself on someone who has hurt you, you hurt them in return.

7. That was how he could revenge himself on those people who had mocked and robbed him.