Definition of: helix

(hē′liks) noun plural he·lix·es or hel·i·ces (hel′·ə·sēz)
1. Geom. A line, thread, wire, or the like, curved into a shape such as it would assume if wound in a single layer round a cylinder; a form like a screw thread.
2. Any spiral.
3. Anat. The recurved border of the external ear.
4. Archit. A small volute. [<L, a spiral <Gk.]