A turn signal is read as announcing a change of direction before you make it. Dream books link it to communicating your intentions clearly, or to signals given and ignored in relationships.
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.