It opens its white mouth wide as a warning. Dream books read the cottonmouth as a clear display of threat and as a defensive stance near water and feeling.
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.