hel·i·coid 
(hĕlĭ-koid′, hēlĭ-)
(hĕlĭ-koid′, hēlĭ-)adj.
Arranged in or having the approximate shape of a flattened coil or spiral.
n.
Mathematics
Mathematics
A surface in the form of a coil or screw.
[Greek helikoeidēs : helix, helik-, spiral; see HELIX + -oeidēs, -oid.]
helicoida helicoid generated by rotating and translating a line at a constant rate about an axis to which it is perpendicular