The Collaborative International Dictionary of English v.0.48:

Ahead \A*head"\, adv. [Pref. a- + head.]
   1. In or to the front; in advance; onward.
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            The island bore but a little ahead of us.
                                                  --Fielding.
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   2. Headlong; without restraint. [Obs.] --L'Estrange.
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   To go ahead.
      (a) To go in advance.
      (b) To go on onward.
      (c) To push on in an enterprise. [Colloq]

   To get ahead of.
      (a) To get in advance of.
      (b) To surpass; to get the better of. [Colloq.]
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