If the aboveThis argument is omitted then the command raises $widget so that it is above all of its siblings in the stacking order (it will not be obscured by any siblings and will obscure any siblings that overlap it). If aboveThis is specified then it must be the path name of a window that is either a sibling of $widget or the descendant of a sibling of $widget. In this case the raise command will insert $widget into the stacking order just above aboveThis (or the ancestor of aboveThis that is a sibling of $widget); this could end up either raising or lowering $widget.