Geometric Center snap

Use the Geometric Center snap to snap to the centroid of another entity. You can snap to the geometric center of any closed polyline or spline. To snap to the geometric center, you must select a visible portion of the entity.  

To set the Geometric Center snap

Do one of the following to choose Geometric Center ():    

    On the ribbon, choose Draw > Geometric Center (in Entity Snaps).

    On the menu, choose Tools > Entity Snaps > Geometric Center.

    On the Entity Snaps toolbar, click the Geometric Center tool.

    Type gcenter and then press Enter.