The waist is read as balance between upper and lower, mind and instinct. Concern about it reflects self-image and how you feel about your body.
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.