acerbity acid acidity acidulousness acrimony animus antagonism antipathy asperity bad blood bad feeling bile bitter feeling bitter resentment bitterness bitterness of spirit causticity choler contempt detestation disaffinity enmity feud gall gnashing of teeth hard feelings hardheartedness hatred heartburning hostility ill blood ill feeling ill will immediate dislike loathing malevolence malice personality conflict rancor rankling resentment slow burn soreness sourness spleen vendetta venom virulence vitriol