Related Clues:

• A three-dimensional spiral
• Fastener with a tapered threaded shank
• 'Spiral structure, DNA is a double one (5)'
• It may pay you to get the thread of this
• You need thread for this but no needle
• They work on baord at last with thread
• It needs thread to get the boat going
• The southern complement gets the thread of it (5)
• The southern complement has a thread
• Do this to the nut behind the ship
• Door-hinge holder
• One whose head is turned
• Turnkey
• Fifty-one in a spell revealing half their DNA?
• See 9