Can someone identify this babel from visual studio 2010?

This image came from a class diagram and it was in the property section开发者_开发百科 if that information helps

I've only seen that in the Data designer of the Entity Framework, not the Class Diagram.

In the EF Designer, it means "Complex Type", also known as "Value Type", because it doesn't have a key of its own. You can see it in the picture here:

http://blogs.msdn.com/b/adonet/archive/2009/05/28/poco-in-the-entity-framework-part-2-complex-types-deferred-loading-and-explicit-loading.aspx

Click on the picture to make it bigger.