The Collaborative International Dictionary of English v.0.48:

Vexation \Vex*a"tion\, n. [L. vexatio: cf. F. vexation.]
   1. The act of vexing, or the state of being vexed; agitation;
      disquiet; trouble; irritation.
      [1913 Webster]

            Passions too violent . . . afford us nothing but
            vexation and pain.                    --Sir W.
                                                  Temple.
      [1913 Webster]

            Those who saw him after a defeat looked in vain for
            any trace of vexation.                --Macaulay.
      [1913 Webster]

   2. The cause of trouble or disquiet; affliction.
      [1913 Webster]

            Your children were vexation to your youth. --Shak.
      [1913 Webster]

   3. A harassing by process of law; a vexing or troubling, as
      by a malicious suit. --Bacon.
      [1913 Webster]

   Syn: Chagrin; agitation; mortification; uneasiness; trouble;
        grief; sorrow; distress. See Chagrin.
        [1913 Webster]

WordNet (r) 3.0 (2006):

vexation
    n 1: anger produced by some annoying irritation [syn:
         annoyance, chafe, vexation]
    2: the psychological state of being irritated or annoyed [syn:
       irritation, annoyance, vexation, botheration]
    3: something or someone that causes anxiety; a source of
       unhappiness; "New York traffic is a constant concern"; "it's
       a major worry" [syn: concern, worry, headache,
       vexation]
    4: the act of troubling or annoying someone [syn: annoyance,
       annoying, irritation, vexation]

Moby Thesaurus II by Grady Ward, 1.0:

133 Moby Thesaurus words for "vexation":
   abomination, affliction, aggravation, agitation, all-overs, angst,
   annoyance, anxiety, anxiety hysteria, anxiety neurosis,
   anxious bench, anxious concern, anxious seat, anxiousness,
   apprehension, apprehensiveness, atrocity, bad, bad news, bane,
   bedevilment, befoulment, blight, bore, bother, botheration,
   bothering, bothersomeness, bugbear, burden, calamity,
   cankerworm of care, care, concern, concernment, corruption,
   crashing bore, crushing burden, crying evil, curse, damage, death,
   defilement, despoliation, destruction, detriment, devilment,
   difficulty, disapprobation, disapproval, discontent, disease,
   displeasure, disquiet, disquietude, dissatisfaction, distress,
   disturbance, dogging, downer, drag, dread, evil, exasperation,
   fear, foreboding, forebodingness, grievance, harassment, harm,
   harrying, havoc, headache, hounding, hurt, ill, infection,
   infliction, injury, inquietude, irking, irritation, malaise,
   mischief, misgiving, molestation, nemesis, nervous strain,
   nervous tension, nervousness, nuisance, open wound, outrage,
   overanxiety, persecution, perturbation, pest, pestilence,
   pins and needles, plague, poison, pollution, problem, provocation,
   provoking, pucker, resentfulness, resentment, running sore,
   scourge, solicitude, stew, strain, suspense, tension, the worst,
   thorn, torment, toxin, trial, trouble, uneasiness, unquietness,
   upset, venom, vexatiousness, vexing, visitation, woe, worriment,
   worry, wrong, zeal



Bouvier's Law Dictionary, Revised 6th Ed (1856):

VEXATION. The injury or damage which, is suffered in consequence of the
tricks of another.