A hat box is read as roles and identities kept in storage, ready to be worn again. Dream books link it to elegance, old occasions and a self you might take out once more.
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.