The Collaborative International Dictionary of English v.0.48:

Verve \Verve\, n. [F.]
   Excitement of imagination such as animates a poet, artist, or
   musician, in composing or performing; rapture; enthusiasm;
   spirit; energy.
   [1913 Webster]

WordNet (r) 3.0 (2006):

verve
    n 1: an energetic style [syn: vitality, verve]

Moby Thesaurus II by Grady Ward, 1.0:

127 Moby Thesaurus words for "verve":
   active fancy, aggressiveness, alacrity, animal spirits, animation,
   anxiety, anxiousness, appetite, ardency, ardor, avidity, avidness,
   bang, bounce, breathless impatience, breeziness, brio, briskness,
   bubbliness, buoyancy, capersomeness, cheerful readiness,
   coltishness, dash, drive, eagerness, ebullience, ecstasy,
   effervescence, elan, elasticity, energy, enterprise, enthusiasm,
   esprit, excited imagination, excitement, exuberance, fervency,
   fervent imagination, fervidness, fervor, fire, flair, flourish,
   forwardness, friskiness, frolicsomeness, furor, fury, gaiety,
   gamesomeness, gayness, get-up-and-go, ginger, gust, gusto, heart,
   heartiness, heat, heated imagination, impassionedness, impatience,
   initiative, keen desire, keenness, kick, life, liveliness,
   lively imagination, lurid imagination, moxie, oomph, panache,
   passion, passionateness, pep, pepper, peppiness, piquancy,
   piss and vinegar, pizzazz, playfulness, poignancy, poop,
   promptness, punch, pungency, push, quickness, raciness, readiness,
   relish, resiliency, rollicksomeness, rompishness, savor,
   skittishness, snap, soul, sparkle, spirit, spiritedness, spirits,
   sportiveness, sprightliness, spring, spunk, starch, thrust,
   vehemence, vigor, vim, vitality, vivaciousness, vivacity,
   vivacity of imagination, vivid imagination, vividness, warmth,
   warmth of feeling, wild imagination, zeal, zest, zestfulness, zing,
   zip