#Gregorian_calendar_month  a month in the Gregorian calendar
  supertype:  #calendar_month__month  one of the twelve divisions of the calendar year; "he paid the bill last month"
  subtype:  #January__Jan  the first month of the year; begins 10 days after the winter solstice
  subtype:  #February__Feb  the month following January and preceding March
  subtype:  #March__Mar  the month following February and preceding April
  subtype:  #April__Apr  the month following March and preceding May
  subtype:  #May  the month following April and preceding June
  subtype:  #June  the month following May and preceding July
  subtype:  #July  the month following June and preceding August
  subtype:  #August__Aug  the month following July and preceding September
  subtype:  #September__Sep__Sept  the month following August and preceding October
  subtype:  #October__Oct  the month following September and preceding November
  subtype:  #November__Nov  the month following October and preceding December
  subtype:  #December__Dec  the last (12th) month of the year

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