captor vs monitor

captor

noun
  • One who catches or has caught or captured something or someone. 

  • One who is holding a captive or captives. 

monitor

noun
  • Someone who watches over something; a person in charge of something or someone. 

  • A monitor lizard. 

  • One of a class of relatively small armored warships with only one or two turrets (but often carrying unusually large guns for a warship of its size), usually designed for shore bombardment or riverine warfare rather than open-ocean combat. 

  • A device similar to a television set used as to give a graphical display of the output from a computer. 

  • A device that detects and informs on the presence, quantity, etc., of something. 

  • A program for viewing and editing. 

  • A tool holder, as for a lathe, shaped like a low turret, and capable of being revolved on a vertical pivot so as to bring the several tools successively into position. 

  • A studio monitor or loudspeaker. 

  • A monitor nozzle. 

verb
  • To watch over; to guard. 

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