The Collaborative International Dictionary of English v.0.48:

Spunky \Spunk"y\ (-[y^]), a. [Compar. Spunkier (-[i^]*[~e]r);
   superl. Spunkiest.]
   Full of spunk; quick; spirited. [Colloq.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

spunky
    adj 1: showing courage; "the champion is faced with a feisty
           challenger" [syn: feisty, plucky, spunky]
    2: willing to face danger [syn: game, gamy, gamey,
       gritty, mettlesome, spirited, spunky]

Moby Thesaurus II by Grady Ward, 1.0:

37 Moby Thesaurus words for "spunky":
   beany, bold, bulldoggish, combustible, courageous, dauntless,
   doughty, explosive, fearless, fiery, game, gamy, gritty, gutsy,
   gutty, hasty, high-spirited, hot, hot-tempered, hotheaded,
   mettlesome, nervy, passionate, peppery, pertinacious, plucky,
   quick, quick-tempered, red-blooded, resolute, short-tempered,
   spirited, spiritful, tenacious, tough, unfearing, volcanic