Выражение встречается в следующем контексте:

The GeometryBag coclass is not considered to be a top-level geometry; it is a collection of any kind of object that supports the IGeometry interface, which is just about every object in the geometry object model including other GeometryBags. Geometry bags are used for various operations within ArcObjects, but some operations assume that only certain classes of Geometry objects are in the bag.

Заранее спасибо=)