Small and protective, the thimble stands for guarding yourself during careful, repetitive work. Dream books see it as quiet diligence and the modest shields that let you keep going.
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.