key fob vs keyholder

key fob

noun
  • An item carried on a key ring either as decoration or security. 

  • A passive wireless electronic device that usually uses RFID technology to control access to buildings, containers, computers, etc. by being placed near a detector. 

  • An active wireless electronic device that controls access to buildings or vehicles, such as a remote control for a car door lock. 

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. 

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