Library /sys$common/syshlp/dce$cdsbrowser.hlb Glossary, Root  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The root is the top directory in the namespace. It is
  designated by a "/.:".

  The logical picture of a namespace is a hierarchical
  tree of all the directories in a namespace, with the
  root directory at the top, and one or more levels of
  directories beneath the root.