helical

adj. spiral, coiled

A helix (pl: helices), from the Greek word έλικας/έλιξ, is a twisted shape like a spring, screw or a spiral (correctly termed helical) staircase. Helices are important in biology, as DNA is helical and many proteins have helical substructures, known as alpha helices.Helices can be either right-handed or left-handed. With the line of sight being the helical axis, if clockwise movement of the helix corresponds to axial movement away from the observer, then it is a right-handed helix. If counter-clockwise movement corresponds to axial movement away from the observer, it is a left-handed helix. Handedness (or chirality) is a property of the helix, not of the perspective: a right-handed helix cannot be turned or flipped to look like a left-handed one unless it is viewed through a mirror, and vice versa.
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Adjective
1. in the shape of a coil
(synonym) coiling, spiral, spiraling, volute, voluted, whorled, turbinate
(similar) coiled

(a.)
Of or pertaining to, or in the form of, a helix; spiral; as, a helical staircase; a helical spring.
  

adj.
پيچ در پيچ, پيچ دار