neckplate

noun4

1. •
   A piece of armour worn around the throat or neck; a gorget.
2. •
   A small, typically rectangular plate on the neck of a guitar (or bass, etc) through which screws are threaded to attach the neck to the body.

   • Maple neck with rosewood fingerboard only; commemorative neckplate. — 2008
3. •
   An armor panel on a helmet which protects the neck.

   • The shot went half a shaft-length deep, slanting from the third neckplate of his helmet toward the base of his left ear. — 2001
4. •
   A plate, used in tracheostomy, which prevents the tube from descending into the trachea.