What does the arrow in the attached image mean?

[david.livshin]

What does the arrow to AboutUs in the attached image mean?

[llegrand]

It indicates there is sub-levels (sub-categories)  in the main level
Click on it and it will expand and list the additional 

[david.livshin]

I tried to delete it but getting:

Warning: This content cannot be deleted as it is currently assigned as the default store account terms!

.
Which in fact is an error message as it refuses to delete the item.

If not delete, can I at least move it out to become a main level and not a sub-level item.

[Basara]

Hi.
You need to check your store settings.
https://abantecart.atlassian.net/wiki/spaces/AD/pages/6848513/Account+Terms

[david.livshin]

Set to "---None---.