WordNet (r) 3.0 (2006):

hellcat
    n 1: a malicious woman with a fierce temper [syn: vixen,
         harpy, hellcat]

Moby Thesaurus II by Grady Ward, 1.0:

79 Moby Thesaurus words for "hellcat":
   Jezebel, Mafioso, Young Turk, adventurer, adventuress, beast,
   beldam, berserk, berserker, bitch-kitty, bomber, bravo, brazenface,
   brute, bucko, bully, bullyboy, cutthroat, daredevil, demon,
   desperado, devil, dragon, fiend, fire-eater, firebrand, fury, goon,
   gorilla, grimalkin, gunman, gunsel, hag, hardnose, harum-scarum,
   hell-raiser, hellhag, hellhound, hellion, holy terror, hood,
   hoodlum, hothead, hotspur, incendiary, killer, mad dog, madbrain,
   madcap, monster, mugger, rantipole, rapist, revolutionary, rough,
   rowdy, ruffian, savage, she-devil, she-wolf, siren, spitfire,
   termagant, terror, terrorist, thug, tiger, tigress, tough,
   tough guy, ugly customer, violent, virago, vixen, wild beast,
   wild man, wildcat, witch, wolf