Threaded nails are a type of fastener that is used to join two pieces of material together. They have a threaded shaft that is driven into the material, and the head of the nail is designed to hold the two pieces together. The crossword solution for the term 'threaded nail' is 'SCREW, ' which is an appropriate term for this type of fastener. A SCREW is a type of fastener that has a helical ridge or thread on its surface, which allows it to be driven into the material with a screwdriver or other tool.