The Collaborative International Dictionary of English v.0.48:

Bob \Bob\, v. t. [imp. & p. p. Bobbed; p. pr. & vb. n.
   Bobbing.] [OE. bobben. See Bob, n.]
   1. To cause to move in a short, jerking manner; to move (a
      thing) with a bob. "He bobbed his head." --W. Irving.
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   2. To strike with a quick, light blow; to tap.
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            If any man happened by long sitting to sleep . . .
            he was suddenly bobbed on the face by the servants.
                                                  --Elyot.
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   3. To cheat; to gain by fraud or cheating; to filch.
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            Gold and jewels that I bobbed from him. --Shak.
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   4. To mock or delude; to cheat.
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            To play her pranks, and bob the fool,
            The shrewish wife began.              --Turbervile.
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   5. To cut short; as, to bob the hair, or a horse's tail.
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