1. [n]  belligerence aroused by a real or supposed wrong (personified as one of the deadly sins)
2. [n]  a strong emotion; a feeling that is oriented toward some real or supposed grievance
3. [n]  the state of being angry
4. [v]  make angry; "The news angered him"
5. [v]  become angry; "He angers easily"

Anger
Explains how to recognize anger and transform it into a productive emotion

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1. \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.
   

2. \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.
   

the emotion of instant displeasure on account of something evil that presents itself to our view. In itself it is an original susceptibility of our nature, just as love is, and is not necessarily sinful. It may, however, become sinful when causeless, or excessive, or protracted (Matt. 5:22; Eph. 4:26; Col. 3:8). As ascribed to God, it merely denotes his displeasure with sin and with sinners (Ps. 7:11).