What does this icon mean in Field List?

[rmitchell]

What does this icon mean in my Field List? Sorry if this is a stupid question but I can't find anywhere a list of icons and what they mean, this field seems to have appeared in my field list and I don't know how or why.

[Seth_C_Bauer · Accepted solution]

@rmitchell It means that you created a group. This is automatically created if you create a clustered group in a visual. The "Month" in your snapshot should be an additional field, and I assume you have the original "Month" with no icon. If this was accidental, you can just delete it.

To create a group, you can click on the elipses of any field and an option way down near the bottom is "New Group". Or, as you probably have found out, a group is created if you build one when using a supporting visual.