The Southern Cross guided sailors in southern seas, so it is read as direction, faith and finding your bearings far from home. It speaks of guidance in unfamiliar places.
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.