WordNet (r) 3.0 (2006):

short-tempered
    adj 1: quickly aroused to anger; "a hotheaded commander" [syn:
           choleric, irascible, hotheaded, hot-tempered,
           quick-tempered, short-tempered]

Moby Thesaurus II by Grady Ward, 1.0:

32 Moby Thesaurus words for "short-tempered":
   abrupt, acerbic, acid, acidulous, acrimonious, bearish, bluff,
   brusque, caustic, crabbed, crabby, crusty, curt, disagreeable,
   discourteous, grouchy, gruff, irascible, irritable, peevish,
   peremptory, petulant, rude, short, shrewish, snappish, surly, tart,
   terse, testy, touchy, waspish