Corkscrew's shape (5)
I believe the answer is:
helix
'corkscrew's shape' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for helix that I've seen before include "Three-dimensional object shaped like a corkscrew" , "Structure made up of a continuous series of loops" , "One of two DNA spirals" , "A three-dimensional spiral" , "Spiral shape" .)