syrinx:

Syrinx was one of those versatile virgins of Arcadia, who, on being pursued by Pan beside the river Ladon, turned herself into a reed, from which Pan made his pipes, so giving her name to various tubular structures, eg syriges, and syrinxes, which are tubular or slit-like cavities in or close to the central canal of the cervical cord. They may extend up or down.

-Oxford Handbook of Clinical Medicine (My Best Friend)