Source : Webster's Revised Unabridged Dictionary (1913)

Dark \Dark\ (d[aum]rk), a. [OE. dark, derk, deork, AS. dearc,
   deorc; cf. Gael. & Ir. dorch, dorcha, dark, black, dusky.]
   1. Destitute, or partially destitute, of light; not
      receiving, reflecting, or radiating light; wholly or
      partially black, or of some deep shade of color; not
      light-colored; as, a dark room; a dark day; dark cloth;
      dark paint; a dark complexion.

            O dark, dark, dark, amid the blaze of noon,
            Irrecoverably dark, total eclipse Without all hope
            of day!                               --Milton.

            In the dark and silent grave.         --Sir W.
                                                  Raleigh.

   2. Not clear to the understanding; not easily seen through;
      obscure; mysterious; hidden.

            The dark problems of existence.       --Shairp.

            What may seem dark at the first, will afterward be
            found more plain.                     --Hooker.

            What's your dark meaning, mouse, of this light word?
                                                  --Shak.

   3. Destitute of knowledge and culture; in moral or
      intellectual darkness; unrefined; ignorant.

            The age wherein he lived was dark, but he Could not
            want light who taught the world to see. --Denhan.

            The tenth century used to be reckoned by medi[ae]val
            historians as the darkest part of this intellectual
            night.                                --Hallam.

   4. Evincing black or foul traits of character; vile; wicked;
      atrocious; as, a dark villain; a dark deed.

            Left him at large to his own dark designs. --Milton.

   5. Foreboding evil; gloomy; jealous; suspicious.

            More dark and dark our woes.          --Shak.

            A deep melancholy took possesion of him, and gave a
            dark tinge to all his views of human nature.
                                                  --Macaulay.

            There is, in every true woman-s heart, a spark of
            heavenly fire, which beams and blazes in the dark
            hour of adversity.                    --W. Irving.

   6. Deprived of sight; blind. [Obs.]

            He was, I think, at this time quite dark, and so had
            been for some years.                  --Evelyn.

   Note: Dark is sometimes used to qualify another adjective;
         as, dark blue, dark green, and sometimes it forms the
         first part of a compound; as, dark-haired, dark-eyed,
         dark-colored, dark-seated, dark-working.

   {A dark horse}, in racing or politics, a horse or a candidate
      whose chances of success are not known, and whose
      capabilities have not been made the subject of general
      comment or of wagers. [Colloq.]

   {Dark house}, {Dark room}, a house or room in which madmen
      were confined. [Obs.] --Shak.

   {Dark lantern}. See {Lantern}. -- The

   {Dark Ages}, a period of stagnation and obscurity in
      literature and art, lasting, according to Hallam, nearly
      1000 years, from about 500 to about 1500 A. D.. See
      {Middle Ages}, under {Middle}.

   {The Dark and Bloody Ground}, a phrase applied to the State
      of Kentucky, and said to be the significance of its name,
      in allusion to the frequent wars that were waged there
      between Indians.

   {The dark day}, a day (May 19, 1780) when a remarkable and
      unexplained darkness extended over all New England.

   {To keep dark}, to reveal nothing. [Low]

Dark \Dark\, n.
   1. Absence of light; darkness; obscurity; a place where there
      is little or no light.

            Here stood he in the dark, his sharp sword out.
                                                  --Shak.

   2. The condition of ignorance; gloom; secrecy.

            Look, what you do, you do it still i' th' dark.
                                                  --Shak.

            Till we perceive by our own understandings, we are
            as muc? in the dark, and as void of knowledge, as
            before.                               --Locke.

   3. (Fine Arts) A dark shade or dark passage in a painting,
      engraving, or the like; as, the light and darks are well
      contrasted.

            The lights may serve for a repose to the darks, and
            the darks to the lights.              --Dryden.

Dark \Dark\, v. t.
   To darken to obscure. [Obs.] --Milton.

Source : WordNet®

dark
     adj 1: devoid or partially devoid of light or brightness; shadowed
            or black or somber-colored; "sitting in a dark
            corner"; "a dark day"; "dark shadows"; "the theater is
            dark on Mondays"; "dark as the inside of a black cat"
            [ant: {light}]
     2: (used of color) having a dark hue; "dark green"; "dark
        glasses"; "dark colors like wine red or navy blue" [ant: {light}]
     3: brunet (used of hair or skin or eyes); "dark eyes"
     4: stemming from evil characteristics or forces; wicked or
        dishonorable; "black deeds"; "a black lie"; "his black
        heart has concocted yet another black deed"; "Darth Vader
        of the dark side"; "a dark purpose"; "dark undercurrents
        of ethnic hostility"; "the scheme of some sinister
        intelligence bent on punishing him"-Thomas Hardy [syn: {black},
         {sinister}]
     5: causing dejection; "a blue day"; "the dark days of the war";
        "a week of rainy depressing weather"; "a disconsolate
        winter landscape"; "the first dismal dispiriting days of
        November"; "a dark gloomy day"; "grim rainy weather" [syn:
         {blue}, {depressing}, {disconsolate}, {dismal}, {dispiriting},
         {gloomy}, {grim}]
     6: secret; "keep it dark"; "the dark mysteries of Africa and
        the fabled wonders of the East"
     7: showing a brooding ill humor; "a dark scowl"; "the
        proverbially dour New England Puritan"; "a glum, hopeless
        shrug"; "he sat in moody silence"; "a morose and
        unsociable manner"; "a saturnine, almost misanthropic
        young genius"- Bruce Bliven; "a sour temper"; "a sullen
        crowd" [syn: {dour}, {glowering}, {glum}, {moody}, {morose},
         {saturnine}, {sour}, {sullen}]
     8: lacking enlightenment or knowledge or culture; "this
        benighted country"; "benighted ages of barbarism and
        superstition"; "the dark ages"; "a dark age in the history
        of education" [syn: {benighted}]
     9: marked by difficulty of style or expression; "much that was
        dark is now quite clear to me"; "those who do not
        appreciate Kafka's work say his style is obscure" [syn: {obscure}]
     10: having skin rich in melanin pigments; "National Association
         for the Advancement of Colored People"; "the dark races";
         "dark-skinned peoples" [syn: {colored}, {coloured}, {dark-skinned}]
     11: not giving performances; closed; "the theater is dark on
         Mondays"

dark
     n 1: absence of light or illumination [syn: {darkness}] [ant: {light}]
     2: absence of moral or spiritual values; "the powers of
        darkness" [syn: {iniquity}, {wickedness}, {darkness}]
     3: an unilluminated area; "he moved off into the darkness"
        [syn: {darkness}, {shadow}]
     4: the time after sunset and before sunrise while it is dark
        outside [syn: {night}, {nighttime}] [ant: {day}]
     5: an unenlightened state; "he was in the dark concerning their
        intentions"; "his lectures dispelled the darkness" [syn: {darkness}]