General terms:
* Spiral: A general term for a shape that curves around a central point.
* Coil: A winding or twisting structure.
* Screw: A helical shape used for fastening.
* Volute: A spiral or scroll-shaped ornament.
* Curl: A tight spiral or twist.
Specific to biological contexts:
* Double helix: The structure of DNA.
* Alpha helix: A common secondary structure in proteins.
* Coil: A term used for protein structures.
Other:
* Spira: A Latin word for helix.
* Vortix: A swirling vortex.
The best word to use will depend on the specific context and what you want to emphasize.