The Collaborative International Dictionary of English v.0.48:

Quicken \Quick"en\, v. t. [imp. & p. p. quickened; p. pr. &
   vb. n. Quickening.] [AS. cwician. See Quick, a.]
   1. To make alive; to vivify; to revive or resuscitate, as
      from death or an inanimate state; hence, to excite; to,
      stimulate; to incite.
      [1913 Webster]

            The mistress which I serve quickens what's dead.
                                                  --Shak.
      [1913 Webster]

            Like a fruitful garden without an hedge, that
            quickens the appetite to enjoy so tempting a prize.
                                                  -- South.
      [1913 Webster]

   2. To make lively, active, or sprightly; to impart additional
      energy to; to stimulate; to make quick or rapid; to
      hasten; to accelerate; as, to quicken one's steps or
      thoughts; to quicken one's departure or speed.
      [1913 Webster]

   3. (Shipbuilding) To shorten the radius of (a curve); to make
      (a curve) sharper; as, to quicken the sheer, that is, to
      make its curve more pronounced.
      [1913 Webster]

   Syn: To revive; resuscitate; animate; reinvigorate; vivify;
        refresh; stimulate; sharpen; incite; hasten; accelerate;
        expedite; dispatch; speed.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Quickening \Quick"en*ing\, n.
   1. The act or process of making or of becoming quick.
      [1913 Webster]

   2. (Physiol.) The first motion of the fetus in the womb felt
      by the mother, occurring usually about the middle of the
      term of pregnancy. It has been popularly supposed to be
      due to the fetus becoming possessed of independent life.
      [1913 Webster]

WordNet (r) 3.0 (2006):

quickening
    n 1: the process of showing signs of life; "the quickening of
         seed that will become ripe grain"
    2: the stage of pregnancy at which the mother first feels the
       movements of the fetus
    3: the act of accelerating; increasing the speed [syn:
       acceleration, quickening, speedup] [ant:
       deceleration]

Moby Thesaurus II by Grady Ward, 1.0:

53 Moby Thesaurus words for "quickening":
   acceleration, activating, animating, animation, animative, bracing,
   clarification, double time, double-quick, double-quick time, drive,
   easing, energizing, enlivening, enlivenment, exhilarating,
   exhilaration, exhilarative, expediting, expedition, facilitation,
   festination, forced march, forwarding, getaway, hastening,
   hurrying, impetus, invigorating, invigoration, invigorative,
   life-giving, pickup, revitalization, revival, rousing,
   simplification, simplifying, smoothing, speeding, speedup, step-up,
   stimulating, stimulation, stimulative, streamlining, thrust, tonic,
   viable, vitalization, vitalizing, vivification, vivifying