The center of gravity (centroid).
[Visual Basic 6.0] Property Centroid As IPoint
[Visual Basic .NET] Public ReadOnly Property Centroid As IPoint
[C#] public IPoint Centroid {get;}
[Java] public IPoint getCentroid() throws IOException, AutomationException
[C++] HRESULT get_Centroid( IPoint** Center );
Returns the Centroid of the 2 (or 2.5) Dimensional figure. The Centroid is the center of the weighted area.
The Centroid does not always occur inside the Area of the geometry. The Centroid is not the same as the center of the geometry or the Envelope binding the geometry (but it may be if and only if that is also the center of the weighted area).

IArea Interface | IArea.QueryCentroid Method | IArea.Centroid Property | IArea.LabelPoint Property | IArea.QueryLabelPoint Method