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1)
#4,828
Common
Meaning
    1. not yet known; unknown; strange
      Antonym: 既知 (きち)
      Sophie had been looking forward to getting another letter from the unknown sender.
Forms
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8)
#18,143
Common
Meaning
    1. mathematics
      (an) unknown; unknown number; variable
      The symbol "x" usually stands for an unknown quantity in mathematics.
    2. unknown quantity; not yet known
Forms
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