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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   hr \hr\ n. [abbreviation]
      An abbreviation for hour, the period of time equal to
      1/24th of a day.
      Syn: hour, 60 minutes.
           [WordNet 1.5] HSV-1
           HS1