[1] : The Collaborative International Dictionary of English v.0.48

ahead \ahead"\, adv. pref. a- + head.
   1. in or to the front; in advance; onward.
      1913 webster

            the island bore but a little ahead of us.
                                                  --fielding.
      1913 webster

   2. headlong; without restraint. obs. --l'estrange.
      1913 webster

   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.
          1913 webster
see also:
to go ahead to get ahead of 

[2] : WordNet (r) 2.0

ahead
     adj : having the leading position or higher score in a contest;
           "he is ahead by a pawn"; "the leading team in the
           pennant race" syn: aheadp, in the lead, leading
     adv 1: at or in the front; "i see the lights of a town ahead"; "the
            road ahead is foggy"; "staring straight ahead"; "we
            couldn't see over the heads of the people in front";
            "with the cross of jesus marching on before" syn: in
            front, before
     2: toward the future; forward in time; "i like to look ahead in
        imagination to what the future may bring"; "i look forward
        to seeing you" syn: forward ant: back, back
     3: in a forward direction; "go ahead"; "the train moved ahead
        slowly"; "the boat lurched ahead"; "moved onward into the
        forest"; "they went slowly forward in the mud" syn: onward,
         onwards, forward, forwards, forrader
     4: ahead of time; in anticipation; "when you pay ahead or in
        advance you receive a discount"; "we like to plan ahead";
        "should have made reservations beforehand" syn: in
        advance, beforehand
     5: to a more advanced or advantageous position; "a young man
        sure to get ahead"; "pushing talented students ahead"
     6: to a different or a more advanced time meaning advanced
        either toward the present or toward the future; "moved
        the appointment ahead from tuesday to monday"; "pushed the
        deadline ahead from tuesday to wednesday"
     7: leading or ahead in a competition; "the horse was three
        lengths ahead going into the home stretch"; "ahead by two
        pawns"; "our candidate is in the lead in the polls"; "way
        out front in the race"; "the advertising campaign put them
        out front in sales" syn: out front, in the lead
see also:
aheadp in the lead leading in front before forward 
back onward onwards forwards forrader 
in advance beforehand out front 

[3] : Moby Thesaurus II by Grady Ward, 1.0

68 moby thesaurus words for "ahead":
   a cut above, above, ahead of time, alee, along, ante, ascendant,
   before, beforehand, beforetime, betimes, better, capping, chosen,
   distinguished, early, eclipsing, eminent, en route to, exceeding,
   excellent, excelling, finer, first, for, fore, foremost,
   foresightedly, forth, forward, forwards, greater, headmost, higher,
   in advance, in anticipation, in ascendancy, in front,
   in the ascendant, in the forefront, in the foreground,
   in the front, in the lead, major, marked, of choice, on, one up on,
   onward, onwards, outstanding, over, precociously, previous, rare,
   rivaling, super, superior, surpassing, to the fore, to the front,
   topping, transcendent, transcendental, transcending, up ahead,
   upper, winning

Ahead >> A Words
Ahead, definition of term: Ahead
ahead_pag1.html

Go Ahead >> G Words
Go Ahead, definition of term: Go Ahead
go+ahead_pag1.html