资料来源 : Webster's Revised Unabridged Dictionary (1913)

Ahead \A*head"\, adv. [Pref. a- + head.]
   1. In or to the front; in advance; onward.

            The island bore but a little ahead of us.
                                                  --Fielding.

   2. Headlong; without restraint. [Obs.] --L'Estrange.

   {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.]