The tear duct is where crying begins, so it is read as feelings close to the surface, ready to be released. A blocked one points to grief held back.
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.