helical (adj.)

• ambagious
• anfractuous
• backhanded
• circuitous
• circular
• cochlear
• deviating
• devious
• digressive
• discursive
• excursive
• indirect
• meandering
• oblique
• orbital
• out-of-the-way
• rotary
• round
• roundabout
• spiral
• turbinate
• verticillate
• volute
• voluted
• whorled