Dry ice turns straight from solid to vapour, making a cold, theatrical fog. It is read as feelings that vanish without melting, or as a dramatic atmosphere that hides what is really there.
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.