What does "ahead" mean?

Ahead: 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.]

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