The Collaborative International Dictionary of English v.0.48:

Nonsense \Non"sense\, n. [Pref. non- + sense: cf. F. nonsens.]
   1. That which is not sense, or has no sense; words, or
      language, which have no meaning, or which convey no
      intelligible ideas; absurdity.
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   2. Trifles; things of no importance.
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   Nonsense verses, lines made by taking any words which
      occur, but especially certain words which it is desired to
      recollect, and arranging them without reference to
      anything but the measure, so that the rhythm of the lines
      may aid in recalling the remembrance of the words.
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   Syn: Folly; silliness; absurdity; trash; balderdash.
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