Source : WordNet®

point of departure
     n 1: a place from which an enterprise or expedition is launched;
          "one day when I was at a suitable jumping-off place I
          decided to see if I could find him"; "my point of
          departure was San Francisco" [syn: {jumping-off place}]
     2: a beginning from which an enterprise is launched; "he uses
        other people's ideas as a springboard for his own";
        "reality provides the jumping-off point for his
        illusions"; "the point of departure of international
        comparison cannot be an institution but must be the
        function it carries out" [syn: {springboard}, {jumping-off
        point}]