Nail

• head

  A projection out from one end; "the head of the nail", "a pinhead is the head of a pin".

• clinch

  The flattened part of a nail or bolt or rivet.

Also contains

• machine bolt

  A bolt with a square or hexagonal head on one end and a threaded shaft on the other...

• stove bolt

  A small machine bolt.

• carriage bolt

  A roundheaded bolt for timber; threaded along part of the shank; inserted into holes...

• kingpin

  Bolt that provides a steering joint in a motor vehicle.

• shank

  Cylinder forming the part of a bolt between the thread and the head.

• expansion bolt

  A bolt that has an attachment that expands as the bolt is driven into a surface.