The Collaborative International Dictionary of English v.0.48:

Spit \Spit\, v. i.
   1. To throw out saliva from the mouth.
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   2. To rain or snow slightly, or with sprinkles.
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            It had been spitting with rain.       --Dickens.
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   To spit on or To spit upon, to insult grossly; to treat
      with contempt. "Spitting upon all antiquity." --South.
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