Appel \Ap`pel"\, n. [F., prop., a call. See {Appeal}, n.]
   (Fencing)
   A tap or stamp of the foot as a warning of intent to attack;
   -- called also {attack}.
   [Webster 1913 Suppl.]

Attack \At*tack"\, v. t. [imp. & p. p. {Attacked}; p. pr. & vb.
   n. {Attacking}.] [F. attaquer, orig. another form of attacher
   to attack: cf. It. attacare to fasten, attack. See {Attach},
   {Tack} a small nail.]
   1. To fall upon with force; to assail, as with force and
      arms; to assault. "Attack their lines." --Dryden.
      
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   2. To assail with unfriendly speech or writing; to begin a
      controversy with; to attempt to overthrow or bring into
      disrepute, by criticism or satire; to censure; as, to
      attack a man, or his opinions, in a pamphlet.
      
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   3. To set to work upon, as upon a task or problem, or some
      object of labor or investigation.
      
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   4. To begin to affect; to begin to act upon, injuriously or
      destructively; to begin to decompose or waste.
      
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            On the fourth of March he was attacked by fever.
                                                  --Macaulay.
      
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            Hydrofluoric acid . . . attacks the glass. --B.
                                                  Stewart.
      
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   Syn: To {Attack}, {Assail}, {Assault}, {Invade}.

   Usage: These words all denote a violent onset; attack being
          the generic term, and the others specific forms of
          attack. To attack is to commence the onset; to assail
          is to make a sudden and violent attack, or to make
          repeated attacks; to assault (literally, to leap upon)
          is to attack physically by a had-to-hand approach or
          by unlawful and insulting violence; to invade is to
          enter by force on what belongs to another. Thus, a
          person may attack by offering violence of any kind; he
          may assail by means of missile weapons; he may assault
          by direct personal violence; a king may invade by
          marching an army into a country. Figuratively, we may
          say, men attack with argument or satire; they assail
          with abuse or reproaches; they may be assaulted by
          severe temptations; the rights of the people may be
          invaded by the encroachments of the crown.
          
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Attack \At*tack"\, v. i.
   To make an onset or attack.
   
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Attack \At*tack"\, n. [Cf. F. attaque.]
   1. The act of attacking, or falling on with force or
      violence; an onset; an assault; -- opposed to defense.
      
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   2. An assault upon one's feelings or reputation with
      unfriendly or bitter words.
      
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   3. A setting to work upon some task, etc.
      
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   4. An access of disease; a fit of sickness.
      
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   5. The beginning of corrosive, decomposing, or destructive
      action, by a chemical agent.
      
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