Source : Webster's Revised Unabridged Dictionary (1913)

Vacation \Va*ca"tion\, n. [F., fr. L. vacatio a being free from
   a duty, service, etc., fr. vacare. See {Vacate}.]
   1. The act of vacating; a making void or of no force; as, the
      vacation of an office or a charter.

   2. Intermission of a stated employment, procedure, or office;
      a period of intermission; rest; leisure.

            It was not in his nature, however, at least till
            years had chastened it, to take any vacation from
            controversy.                          --Palfrey.
      Hence, specifically: 
      (a) (Law) Intermission of judicial proceedings; the space
          of time between the end of one term and the beginning
          of the next; nonterm; recess. ``With lawyers in the
          vacation.'' --Shak.
      (b) The intermission of the regular studies and exercises
          of an educational institution between terms; holidays;
          as, the spring vacation.
      (c) The time when an office is vacant; esp. (Eccl.), the
          time when a see, or other spiritual dignity, is
          vacant.

Source : WordNet®

vacation
     n 1: leisure time away from work devoted to rest or pleasure; "we
          get two weeks of vacation every summer"; "we took a
          short holiday in Puerto Rico" [syn: {holiday}]
     2: the act of making something legally void

vacation
     v : spend or take a vacation [syn: {holiday}]