Swifts spend almost their whole lives in the air, so dream books read them as restlessness, speed and freedom that never quite lands. They can stand for a pace of life that leaves little room to rest.
Has this come up in your dreams before? What was going on in your life then?
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.