with a vengeance

Vengeance \Venge"ance\, n. [F. vengeance, fr. venger to avenge,
   L. vindicare to lay claim to, defend, avenge, fr. vindex a
   claimant, defender, avenger, the first part of which is of
   uncertain origin, and the last part akin to dicere to say.
   See {Diction}, and cf. {Avenge}, {Revenge}, {Vindicate}.]
   1. Punishment inflicted in return for an injury or an
      offense; retribution; -- often, in a bad sense, passionate
      or unrestrained revenge.
      [1913 Webster]

            To me belongeth vengeance and recompense. --Deut.
                                                  xxxii. 35.
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            To execute fierce vengeance on his foes. --Milton.
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   2. Harm; mischief. [Obs.] --Shak.
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   {What a vengeance}, or {What the vengeance}, what! --
      emphatically. [Obs.] "But what a vengeance makes thee
      fly!" --Hudibras. "What the vengeance! Could he not speak
      'em fair?" --Shak.

   {With a vengeance},
      (a) with great violence; as, to strike with a vengeance.
          [Colloq.]
      (b) with even greater intensity; as, to return one's
          insult with a vengeance.
          [1913 Webster + PJC]
    

69 Moby Thesaurus words for "with a vengeance":
      a outrance, a toute outrance, absolutely, all hollow, all out,
      all the way, all to pieces, beyond all bounds, beyond compare,
      beyond comparison, beyond measure, cogently, completely, dead,
      downright, dynamically, effectively, effectually, energetically,
      essentially, extremely, fiercely, flat out, forcefully, forcibly,
      fundamentally, furiously, immeasurably, in the extreme,
      incalculably, indefinitely, infinitely, like blazes, like fury,
      like mad, madly, mightily, most, perfectly, potently, powerfully,
      productively, purely, radically, rigorously, severely, strikingly,
      tellingly, to a fare-you-well, to good account, to good purpose,
      to the backbone, to the full, to the limit, to the marrow,
      to the skies, to the sky, to the utmost, totally, unconditionally,
      unequivocally, utterly, vehemently, venomously, vigorously,
      violently, virulently, wildly, with telling effect