Shapes appearing on their own are read as the mind sorting experience into forms it can hold. A shapeless thing, by contrast, stands for something not yet defined — a feeling or plan without clear outline.
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.