grand duchess

  1. the wife or widow of a grand duke
  2. a woman who has the rank of a grand duke and rules a grand duchy
  3. in czarist Russia, a royal princess

See grand duchess in American Heritage Dictionary 4

noun
  1. The wife or widow of a grand duke.
  2. A woman who is the sovereign of a grand duchy.
  3. The daughter or granddaughter of a czar in the male line.
  4. Used as the title for such a noblewoman.
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