Contracts under the terms of the Hollywood Director's Guild usually allow 6 weeks for a director to assemble a cut of the movie without studio interference as he or she would like it to be seen.
A final cut of the movie that the director has complete artistic control over which often differs greatly from the original theatrical version.
Extra footage not originally contained in the original or theatrical release, re-edited as the director originally intended.
A director's cut is a specially edited version of a film, and less often TV series or video games, that is supposed to represent the director's own approved edit. 'Cut' explicitly refers to the process of film editing: the director's cut is preceded by the rough editor's cut and followed by the final cut meant for the public film release.
