Source : Webster's Revised Unabridged Dictionary (1913)

Antedate \An"te*date`\, v. t. [imp. & p. p. {Antedated}; p. pr.
   & vb. n. {Antedating}.]
   1. To date before the true time; to assign to an earlier
      date; thus, to antedate a deed or a bond is to give it a
      date anterior to the true time of its execution.

   2. To precede in time.

   3. To anticipate; to make before the true time.

            And antedate the bliss above.         --Pope.

            Who rather rose the day to antedate.  --Wordsworth.