Is there a design pattern that describes my solution?

I have to present my project infront of an audience and I would like to describe my method of giving one single class access to my object list and having every other class call it instead of accessing the list itself.

In my code I have called it a "provider" but I have been told that this naming is misleading.. Is there any pattern that describes this scenario? In case it helps: I've put my class diagram down below.

Thank you guys