Have a ball

Meaning:

We can say that we are having a ball if we are really enjoying something. A person who is having a ball doing something is having a lot of fun. We can also say that something "is" or "was" a ball.

Example sentences:

1. I'm having a ball.
2. We had a ball last night at the party.
3. It was a ball.

Example dialogue:

Two friends are talking about one's vacation.

A: Are you having a good time on your vacation?
B: Oh yeah. I'm having a ball. We're going to different restaurants every night, going to see shows, and going dancing on the weekends.
B: Nice! It sounds like you really are having a ball.

Practice:

When was the last time you had a ball?