Source : Webster's Revised Unabridged Dictionary (1913)

Anger \An"ger\, n. [OE. anger, angre, affliction, anger, fr.
   Icel. angr affliction, sorrow; akin to Dan. anger regret,
   Swed. [*a]nger regret, AS. ange oppressed, sad, L. angor a
   strangling, anguish, angere to strangle, Gr. ? to strangle,
   Skr. amhas pain, and to. anguish, anxious, quinsy, and perh.
   awe, ugly. The word seems to have orig. meant to choke,
   squeeze. ?.]
   1. Trouble; vexation; also, physical pain or smart of a sore,
      etc. [Obs.]

            I made the experiment, setting the moxa where . . .
            the greatest anger and soreness still continued.
                                                  --Temple.

   2. A strong passion or emotion of displeasure or antagonism,
      excited by a real or supposed injury or insult to one's
      self or others, or by the intent to do such injury.

            Anger is like A full hot horse, who being allowed
            his way, Self-mettle tires him.       --Shak.

   Syn: Resentment; wrath; rage; fury; passion; ire gall;
        choler; indignation; displeasure; vexation; grudge;
        spleen.

   Usage: {Anger}, {Indignation}, {Resentment}, {Wrath}, {Ire},
          {Rage}, {Fury}. Anger is a feeling of keen displeasure
          (usually with a desire to punish) for what we regard
          as wrong toward ourselves or others. It may be
          excessive or misplaced, but is not necessarily
          criminal. Indignation is a generous outburst of anger
          in view of things which are indigna, or unworthy to be
          done, involving what is mean, cruel, flagitious, etc.,
          in character or conduct. Resentment is often a moody
          feeling, leading one to brood over his supposed
          personal wrongs with a deep and lasting anger. See
          {Resentment}. Wrath and ire (the last poetical)
          express the feelings of one who is bitterly provoked.
          Rage is a vehement ebullition of anger; and fury is an
          excess of rage, amounting almost to madness. Warmth of
          constitution often gives rise to anger; a high sense
          of honor creates indignation at crime; a man of quick
          sensibilities is apt to cherish resentment; the wrath
          and ire of men are often connected with a haughty and
          vindictive spirit; rage and fury are distempers of the
          soul to be regarded only with abhorrence.

Anger \An"ger\, v. t. [imp. & p. p. {Angered}; p. pr. & vb. n.
   {Angering}.] [Cf. Icel. angra.]
   1. To make painful; to cause to smart; to inflame. [Obs.]

            He . . . angereth malign ulcers.      --Bacon.

   2. To excite to anger; to enrage; to provoke.

            Taxes and impositions . . . which rather angered
            than grieved the people.              --Clarendon.

Source : WordNet®

anger
     n 1: a strong emotion; a feeling that is oriented toward some
          real or supposed grievance [syn: {choler}, {ire}]
     2: the state of being angry [syn: {angriness}]
     3: belligerence aroused by a real or supposed wrong
        (personified as one of the deadly sins) [syn: {wrath}, {ire},
         {ira}]
     v 1: make angry; "The news angered him"
     2: become angry; "He angers easily" [syn: {see red}]