Vendetta :  (noun)

1: a feud in which members of the opposing parties murder each other [syn: blood feud]

acrimony, altercation, animosity, animus, argument, avengement, bad blood, bicker, bitter feeling, bitterness, blood feud, brawl, broil, conflict, contention, controversy, dispute, donnybrook, donnybrook fair, embroilment, enmity, feud, fight, fliting, fracas, fuss, getting even, hard feelings, hatred, ill blood, ill feeling, ill will, imbroglio, logomachy, open quarrel, polemic, quarrel, rancor, reprisal, retaliation, revanche, revanchism, revenge, rhubarb, rivalry, row, set-to, sharp words, slanging match, snarl, soreness, sourness, spat, squabble, strife, sweet revenge, tiff, tussle, vengeance, venom, virulence, vitriol, words, wrangle,