Source : Webster's Revised Unabridged Dictionary (1913)

Secret \Se"cret\, n. [F. secret (cf. Pr. secret, Sp. & Pg.
   secreto, It. secreto, segreto), from L. secretum. See
   {Secret}, a.]
   1. Something studiously concealed; a thing kept from general
      knowledge; what is not revealed, or not to be revealed.

            To tell our secrets is often folly; to communicate
            those of others is treachery.         --Rambler.

Secret \Se"cret\, a. [F. secret (cf. Sp.& Pg. secreto, It.
   secreto, segreto), fr. L. secretus, p. p. of secrernere to
   put apart, to separate. See {Certain}, and cf. {Secrete},
   {Secern}.]
   1. Hidden; concealed; as, secret treasure; secret plans; a
      secret vow. --Shak.

            The secret things belong unto the Lord our God; but
            those things which are revealed belong unto us.
                                                  --Deut. xxix.
                                                  29.

   2. Withdraw from general intercourse or notice; in retirement
      or secrecy; secluded.

            There, secret in her sapphire cell, He with the
            Na["i]s wont to dwell.                --Fenton.

   3. Faithful to a secret; not inclined to divulge or betray
      confidence; secretive. [R.]

            Secret Romans, that have spoke the word, And will
            not palter.                           --Shak.

   4. Separate; distinct. [Obs.]

            They suppose two other divine hypostases superior
            thereunto, which were perfectly secret from matter.
                                                  --Cudworth.

   Syn: Hidden; concealed; secluded; retired; unseen; unknown;
        private; obscure; recondite; latent; covert;
        clandestine; privy. See {Hidden}.

Secret \Se"cret\, v. t.
   To keep secret. [Obs.] --Bacon.

Source : WordNet®

secret
     adj 1: not open or public; kept private or not revealed; "a secret
            formula"; "secret ingredients"; "secret talks"
     2: conducted with or marked by hidden aims or methods;
        "clandestine intelligence operations"; "cloak-and-dagger
        activities behind enemy lines"; "hole-and-corner
        intrigue"; "secret missions"; "a secret agent"; "secret
        sales of arms"; "surreptitious mobilization of troops";
        "an undercover investigation"; "underground resistance"
        [syn: {clandestine}, {cloak-and-dagger}, {hole-and-corner(a)},
         {hugger-mugger}, {hush-hush}, {on the quiet(p)}, {surreptitious},
         {undercover}, {underground}]
     3: not openly made known; "a secret marriage"; "a secret bride"
        [syn: {unavowed}]
     4: communicated covertly; "their a secret signal was a wink";
        "secret messages"
     5: not expressed; "secret (or private) thoughts" [syn: {private}]
     6: designed to elude detection; "a hidden room or place of
        concealment such as a priest hole"; "a secret passage";
        "the secret compartment in the desk" [syn: {hidden}]
     7: hidden from general view or use; "a privy place to rest and
        think"; "a secluded romantic spot"; "a secret garden"
        [syn: {privy}, {secluded}]
     8: (of information) given in confidence or in secret; "closet
        information"; "this arrangement must be kept
        confidential"; "their secret communications" [syn: {closet(a)},
         {confidential}]
     9: indulging only covertly; "a closet alcoholic"; "closet
        liberals" [syn: {closet(a)}]
     10: having an import not apparent to the senses nor obvious to
         the intelligence; beyond ordinary understanding;
         "mysterious symbols"; "the mystical style of Blake";
         "occult lore"; "the secret learning of the ancients"
         [syn: {mysterious}, {mystic}, {mystical}, {occult}, {orphic}]
     11: the next to highest level of official classification for
         documents

secret
     n 1: something that should remain hidden from others (especially
          information that is not to be passed on); "the
          combination to the safe was a secret"; "he tried to keep
          his drinking a secret"
     2: information known only to a special group; "the secret of
        Cajun cooking" [syn: {arcanum}]
     3: something that baffles understanding and cannot be
        explained; "how it got out is a mystery"; "it remains one
        of nature's secrets" [syn: {mystery}, {enigma}, {closed
        book}]