A dashed line is a path with gaps — a connection that comes and goes. On a road it marks where you are allowed to cross over, so dream books also read it as permission to change lanes in life.
Where in your waking life have you met something like this lately?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.