keyholder vs machinist

keyholder

noun
  • A device or component for holding a key. 

  • The individual or organisation with access to a cryptographic key. 

  • A dominant partner who controls whether their submissive partner is able or allowed to orgasm or receive sexual stimulation, typically by locking the submissive partner in a chastity belt or chastity cage. 

  • One who holds the key to a building etc. for security reasons. 

machinist

noun
  • One skilled in the use of machine tools for fashioning metal parts or tools out of metal. 

  • A constructor of machines and engines; one versed in the principles of machines. 

  • A person who operates machinery. 

  • A person employed to shift scenery in a theater. 

How often have the words keyholder and machinist occurred in a corpus of books? (source: Google Ngram Viewer )