J curves like a hook, read as catching hold of something or turning back upward after a dip. Dream books also note the names it begins and what they mean to the dreamer.
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.