hard stop vs hour

hard stop

noun
  • A definite time when someone must end a task in order to meet another time commitment. 

  • A mechanical device that limits the travel of a mechanism. 

  • A tactic used by armed police to stop a vehicle believed to contain dangerous criminals. 

  • Synonym of full stop 

hour

noun
  • The time. 

  • A season, moment, or time. 

  • Used after a two-digit hour and a two-digit minute to indicate time. 

  • A time period of sixty minutes; one twenty-fourth of a day. 

  • The set times of prayer, the canonical hours, the offices or services prescribed for these, or a book containing them. 

  • A distance that can be traveled in one hour. 

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