1. In ornithology, voice organ in births: Since Jack loved birds, he had a book about them where he read about the syrinx which was near the place where the bronchi and the trachea link together.
2. In pathology, one of many abnormal tube-shaped structures in the body: One fluid-filled syrinx is a rare neuroglial cavity in the brain stem.
3. In music, a set of panpipes: In the fairy tale, a syrinx, a wind instrument with many parallel pipes bound together, was played by a beautiful fairy.