SP.Taxonomy.Term.isPinnedRoot property (sp.taxonomy)
Gets a Boolean value that indicates if this is a pinned object and the root of the pinned tree.
Applies to: apps for SharePoint | SharePoint Foundation 2013 | SharePoint Server 2013
var value = SP.Taxonomy.Term.get_isPinnedRoot()
Return value
true if the object is pinned and the root of the pinned tree; otherwise, false.