The Collaborative International Dictionary of English v.0.48:

Volley \Vol"ley\, n.; pl. Volleys. [F. vol['e]e; flight, a
   volley, or discharge of several guns, fr. voler to fly, L.
   volare. See Volatile.]
   1. A flight of missiles, as arrows, bullets, or the like; the
      simultaneous discharge of a number of small arms.
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            Fiery darts in flaming volleys flew.  --Milton.
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            Each volley tells that thousands cease to breathe.
                                                  --Byron.
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   2. A burst or emission of many things at once; as, a volley
      of words. "This volley of oaths." --B. Jonson.
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            Rattling nonsense in full volleys breaks. --Pope.
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   3.
      (a) (Tennis) A return of the ball before it touches the
          ground.
      (b) (Cricket) A sending of the ball full to the top of the
          wicket.
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   Half volley.
      (a) (Tennis) A return of the ball immediately after is has
          touched the ground.
      (b) (Cricket) A sending of the ball so that after touching
          the ground it flies towards the top of the wicket.
          --R. A. Proctor.

   On the volley, at random. [Obs.] "What we spake on the
      volley begins work." --Massinger.

   Volley gun, a gun with several barrels for firing a number
      of shots simultaneously; a kind of mitrailleuse.
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WordNet (r) 3.0 (2006):

half volley
    n 1: a tennis return made by hitting the ball immediately after
         it bounces