Source : Webster's Revised Unabridged Dictionary (1913)

Evil \E"vil\ ([=e]"v'l) n.
   1. Anything which impairs the happiness of a being or
      deprives a being of any good; anything which causes
      suffering of any kind to sentient beings; injury;
      mischief; harm; -- opposed to {good}.

            Evils which our own misdeeds have wrought. --Milton.

            The evil that men do lives after them. --Shak.

   2. Moral badness, or the deviation of a moral being from the
      principles of virtue imposed by conscience, or by the will
      of the Supreme Being, or by the principles of a lawful
      human authority; disposition to do wrong; moral offence;
      wickedness; depravity.

            The heart of the sons of men is full of evil.
                                                  --Eccl. ix. 3.

   3. malady or disease; especially in the phrase king's evil,
      the scrofula. [R.] --Shak.

            He [Edward the Confessor] was the first that touched
            for the evil.                         --Addison.

Evil \E*vil\a. [OE. evel, evil, ifel, uvel, AS. yfel; akin to
   OFries, evel, D. euvel, OS. & OHG. ubil, G. ["u]bel, Goth.
   ubils, and perh. to E. over.]
   1. Having qualities tending to injury and mischief; having a
      nature or properties which tend to badness; mischievous;
      not good; worthless or deleterious; poor; as, an evil
      beast; and evil plant; an evil crop.

            A good tree can not bring forth evil fruit. --Matt.
                                                  vii. 18.

   2. Having or exhibiting bad moral qualities; morally corrupt;
      wicked; wrong; vicious; as, evil conduct, thoughts, heart,
      words, and the like.

            Ah, what a sign it is of evil life, When death's
            approach is seen so terrible.         --Shak.

   3. Producing or threatening sorrow, distress, injury, or
      calamity; unpropitious; calamitous; as, evil tidings; evil
      arrows; evil days.

            Because he hath brought up an evil name upon a
            virgin of Israel.                     --Deut. xxii.
                                                  19.

            The owl shrieked at thy birth -- an evil sign.
                                                  --Shak.

            Evil news rides post, while good news baits.
                                                  --Milton.

   {Evil eye}, an eye which inflicts injury by some magical or
      fascinating influence. It is still believed by the
      ignorant and superstitious that some persons have the
      supernatural power of injuring by a look.

            It almost led him to believe in the evil eye. --J.
                                                  H. Newman.

   {Evil speaking}, speaking ill of others; calumny;
      censoriousness.

   {The evil one}, the Devil; Satan.

   Note: Evil is sometimes written as the first part of a
         compound (with or without a hyphen). In many cases the
         compounding need not be insisted on. Examples: Evil
         doer or evildoer, evil speaking or evil-speaking, evil
         worker, evil wishing, evil-hearted, evil-minded.

   Syn: Mischieveous; pernicious; injurious; hurtful;
        destructive; wicked; sinful; bad; corrupt; perverse;
        wrong; vicious; calamitous.

Evil \E"vil\, adv.
   In an evil manner; not well; ill; badly; unhappily;
   injuriously; unkindly. --Shak.

         It went evil with his house.             --1 Chron.
                                                  vii. 23.

         The Egyptians evil entreated us, and affected us.
                                                  --Deut. xxvi.
                                                  6.

Source : WordNet®

evil
     adj 1: morally bad or wrong; "evil purposes"; "an evil influence";
            "evil deeds" [syn: {wicked}] [ant: {good}]
     2: having the nature of vice [syn: {depraved}, {vicious}]
     3: tending to cause great harm [syn: {harmful}, {injurious}]
     4: having or exerting a malignant influence; "malevolent
        stars"; "a malefic force" [syn: {malefic}, {malevolent}, {malign}]

evil
     n 1: morally objectionable behavior [syn: {immorality}, {wickedness},
           {iniquity}]
     2: that which causes harm or destruction or misfortune; "the
        evil that men do lives after them; the good is oft
        interred with their bones"- Shakespeare
     3: the quality of being morally wrong in principle or practice;
        "attempts to explain the origin of evil in the world"
        [syn: {evilness}] [ant: {good}, {good}]

Source : Free On-Line Dictionary of Computing

evil
     
        As used by a {hacker}, implies that some system, program,
        person, or institution is sufficiently maldesigned as to be
        not worth the bother of dealing with.  Unlike the adjectives
        in the cretinous, {losing}, {brain-damaged} series, "evil"
        does not imply incompetence or bad design, but rather a set of
        goals or design criteria fatally incompatible with the
        speaker's.  This usage is more an aesthetic and engineering
        judgment than a moral one in the mainstream sense.  "We
        thought about adding a {Blue Glue} interface but decided it
        was too evil to deal with."  "{TECO} is neat, but it can be
        pretty evil if you're prone to typos."  Often pronounced with
        the first syllable lengthened, as /eeee'vil/.
     
        Compare {evil and rude}.
     
        [{Jargon File}]
     
        (1994-12-12)