The Collaborative International Dictionary of English v.0.48:

Vigil \Vig"il\, n. [OE. vigile, L. vigilia, from vigil awake,
   watchful, probably akin to E. wake: cf. F. vigile. See
   Wake, v. i., and cf. Reveille, Surveillance, Vedette,
   Vegetable, Vigor.]
   1. Abstinence from sleep, whether at a time when sleep is
      customary or not; the act of keeping awake, or the state
      of being awake; sleeplessness; wakefulness; watch. "Worn
      out by the labors and vigils of many months." --Macaulay.
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            Nothing wears out a fine face like the vigils of the
            card table and those cutting passions which attend
            them.                                 --Addison.
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   2. Hence, devotional watching; waking for prayer, or other
      religious exercises.
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            So they in heaven their odes and vigils tuned.
                                                  --Milton.
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            Be sober and keep vigil,
            The Judge is at the gate.             --Neale
                                                  (Rhythm of St.
                                                  Bernard).
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   3. (Eccl.)
      (a) Originally, the watch kept on the night before a
          feast.
      (b) Later, the day and the night preceding a feast.
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                He that shall live this day, and see old age,
                Will yearly on the vigil feast his neighbors,
                And say, "To-morrow is St. Crispian." --Shak.
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      (c) A religious service performed in the evening preceding
          a feast.
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   Vigils of flowers or Watchings of flowers (Bot.), a
      peculiar faculty belonging to the flowers of certain
      plants of opening and closing their petals at certain
      hours of the day. [R.]
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