WordNet (r) 3.0 (2006):

gung ho
    adj 1: very enthusiastic and dedicated

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "gung ho":
   buggy, bugle call, bugs, call to arms, call-up, catchword, clarion,
   clarion call, conscription, enthused, enthusiastic,
   enthusiastic about, exhortation, full of enthusiasm, glowing,
   go for broke, gung-ho, infatuated with, keen, keen on, levy,
   mobilization, muster, nutty, rally, rallying cry, rebel yell,
   recruitment, slogan, trumpet call, war cry, war whoop, warm,
   watchword, zealous