An eruption stands for the moment held-in feeling bursts out. Tradition reads it as an outburst or sudden release of tension, often clearing the way for change once things settle.
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.