A railroad crossing is traditionally read as a point where two paths meet and one must wait. It speaks of timing, patience and respect for forces larger than yourself.
When this appeared in your dream, what were you feeling?
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.