The Collaborative International Dictionary of English v.0.48:

Directory \Di*rect"o*ry\, n.; pl. Directories.
   1. A collection or body of directions, rules, or ordinances;
      esp., a book of directions for the conduct of worship; as,
      the Directory used by the nonconformists instead of the
      Prayer Book.
      [1913 Webster]

   2. A book containing the names and residences of the
      inhabitants of any place, or of classes of them; an
      address book; as, a business directory.
      [1913 Webster]

   3. [Cf. F. directoire.] A body of directors; board of
      management; especially, a committee which held executive
      power in France under the first republic.
      [1913 Webster]

   4. Direction; guide. [R.] --Whitlock.
      [1913 Webster]

The Free On-line Dictionary of Computing (30 December 2018):

directory
directories
folder

    A node in a hierarchical file system which
   contains zero or more other nodes - generally, files or
   other directories.

   The term "folder" is sometimes used in systems such as the
   Macintosh or Microsoft Windows in which directories are
   traditionally depicted as folders (like small briefcases).

   (2007-02-21)