If you apologize to someone, you say that you are sorry for doing something that they disapprove of, that upsets them, or that causes them trouble.

1. He apologized for interrupting her and quickly left.
2. Indeed not more than a week after her terrible accusations she apologized to Michael for what she had said.
3. ‘If I hurt you, I’m sorry.’ — ‘Don’t apologize.’

If you excuse yourself, you give reasons to justify something that you have done and that other people might disapprove of. These reasons are often not very good ones.

4. She was late for work every morning and excused herself by saying that she had overslept.
5. What a fool he’d been to send her that expensive scarf to excuse himself for not having kept the appointment.

• Note that you also excuse yourself when you explain that you have to leave someone to go somewhere else.

6. The doorbell rings. Lewis excuses himself and pushes through the crowd.