#middle_age  the time of life between youth and old age (e.g., between 40 and 60 years of age)
  supertype:  #time_of_life  a period of time during which a person is normally in a particular life state
  part of:  #maturity
  part:  #menopause__climacteric__changeoflife  the time in a woman's life in which the menstrual cycle ends
  part:  #climacteric  a period in a man's life corresponding to menopause

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