Source : Webster's Revised Unabridged Dictionary (1913)

Sign \Sign\, n. [F. signe, L. signum; cf. AS. segen, segn, a
   sign, standard, banner, also fr. L. signum. Cf. {Ensign},
   {Resign}, {Seal} a stamp, {Signal}, {Signet}.]
   That by which anything is made known or represented; that
   which furnishes evidence; a mark; a token; an indication; a
   proof. Specifically:
   (a) A remarkable event, considered by the ancients as
       indicating the will of some deity; a prodigy; an omen.
   (b) An event considered by the Jews as indicating the divine
       will, or as manifesting an interposition of the divine
       power for some special end; a miracle; a wonder.

             Through mighty signs and wonders, by the power of
             the Spirit of God.                   --Rom. xv. 19.

             It shall come to pass, if they will not believe
             thee, neither hearken to the voice of the first
             sign, that they will believe the voice of the
             latter sign.                         --Ex. iv. 8.
   (c) Something serving to indicate the existence, or preserve
       the memory, of a thing; a token; a memorial; a monument.

             What time the fire devoured two hundred and fifty
             men, and they became a sign.         --Num. xxvi.
                                                  10.
   (d) Any symbol or emblem which prefigures, typifles, or
       represents, an idea; a type; hence, sometimes, a picture.

             The holy symbols, or signs, are not barely
             significative; but what they represent is as
             certainly delivered to us as the symbols
             themselves.                          --Brerewood.

             Saint George of Merry England, the sign of victory.
                                                  --Spenser.
   (e) A word or a character regarded as the outward
       manifestation of thought; as, words are the sign of
       ideas.
   (f) A motion, an action, or a gesture by which a thought is
       expressed, or a command or a wish made known.

             They made signs to his father, how he would have
             him called.                          --Luke i. 62.
   (g) Hence, one of the gestures of pantomime, or of a language
       of a signs such as those used by the North American
       Indians, or those used by the deaf and dumb.

   Note: Educaters of the deaf distinguish between natural
         signs, which serve for communicating ideas, and
         methodical, or systematic, signs, adapted for the
         dictation, or the rendering, of written language, word
         by word; and thus the signs are to be distinguished
         from the manual alphabet, by which words are spelled on
         the fingers.
   (h) A military emblem carried on a banner or a standard.
       --Milton.
   (i) A lettered board, or other conspicuous notice, placed
       upon or before a building, room, shop, or office to
       advertise the business there transacted, or the name of
       the person or firm carrying it on; a publicly displayed
       token or notice.

             The shops were, therefore, distinguished by painted
             signs, which gave a gay and grotesque aspect to the
             streets.                             --Macaulay.
   (j) (Astron.) The twelfth part of the ecliptic or zodiac.

   Note: The signs are reckoned from the point of intersection
         of the ecliptic and equator at the vernal equinox, and
         are named, respectively, {Aries} ([Aries]), {Taurus}
         ([Taurus]), {Gemini} (II), {Cancer} ([Cancer]), {Leo}
         ([Leo]), {Virgo} ([Virgo]), {Libra} ([Libra]),
         {Scorpio} ([Scorpio]), {Sagittarius} ([Sagittarius]),
         {Capricornus  ([Capricorn]), {Aquarius} ([Aquarius]),
         {Pisces} ([Pisces]). These names were originally the
         names of the constellations occupying severally the
         divisions of the zodiac, by which they are still
         retained; but, in consequence of the procession of the
         equinoxes, the signs have, in process of time, become
         separated about 30 degrees from these constellations,
         and each of the latter now lies in the sign next in
         advance, or to the east of the one which bears its
         name, as the constellation Aries in the sign Taurus,
         etc.
   (k) (Alg.) A character indicating the relation of quantities,
       or an operation performed upon them; as, the sign +
       (plus); the sign -- (minus); the sign of division /, and
       the like.
   (l) (Med.) An objective evidence of disease; that is, one
       appreciable by some one other than the patient.

   Note: The terms symptom and and sign are often used
         synonymously; but they may be discriminated. A sign
         differs from a symptom in that the latter is perceived
         only by the patient himself. The term sign is often
         further restricted to the purely local evidences of
         disease afforded by direct examination of the organs
         involved, as distinguished from those evidence of
         general disturbance afforded by observation of the
         temperature, pulse, etc. In this sense it is often
         called physical sign.
   (m) (Mus.) Any character, as a flat, sharp, dot, etc.
   (n) (Theol.) That which, being external, stands for, or
       signifies, something internal or spiritual; -- a term
       used in the Church of England in speaking of an ordinance
       considered with reference to that which it represents.

             An outward and visible sign of an inward and
             spiritual grace.                     --Bk. of
                                                  Common Prayer.

   Note: See the Table of {Arbitrary Signs}, p. 1924.

   {Sign manual}.
   (a) (Eng. Law) The royal signature superscribed at the top of
       bills of grants and letter patent, which are then sealed
       with the privy signet or great seal, as the case may be,
       to complete their validity.
   (b) The signature of one's name in one's own handwriting.
       --Craig. Tomlins. Wharton.

   Syn: Token; mark; note; symptom; indication; signal; symbol;
        type; omen; prognostic; presage; manifestation. See
        {Emblem}.

Sign \Sign\, v. i.
   1. To be a sign or omen. [Obs.] --Shak.

   2. To make a sign or signal; to communicate directions or
      intelligence by signs.

   3. To write one's name, esp. as a token of assent,
      responsibility, or obligation.

Sign \Sign\, v. t. [imp. & p. p. {Signed}; p. pr. & vb. n.
   {Signing}.] [OE. seinen to bless, originally, to make the
   sign of the cross over; in this sense fr. ASS. segnian (from
   segn, n.), or OF. seignier, F. signer, to mark, to sign (in
   sense 3), fr. L. signare to mark, set a mark upon, from
   signum. See {Sign}, n.]
   1. To represent by a sign; to make known in a typical or
      emblematic manner, in distinction from speech; to signify.

            I signed to Browne to make his retreat. --Sir W.
                                                  Scott.

   2. To make a sign upon; to mark with a sign.

            We receive this child into the congregation of
            Christ's flock, and do sign him with the sign of the
            cross.                                --Bk. of Com
                                                  Prayer.

   3. To affix a signature to; to ratify by hand or seal; to
      subscribe in one's own handwriting.

            Inquire the Jew's house out, give him this deed, And
            let him sign it.                      --Shak.

   4. To assign or convey formally; -- used with away.

   5. To mark; to make distinguishable. --Shak.

Source : WordNet®

sign
     adj : used of the language of the deaf [syn: {gestural}, {sign(a)},
            {signed}, {sign-language(a)}]

sign
     n 1: a perceptible indication of something not immediately
          apparent (as a visible clue that something has
          happened); "he showed signs of strain"; "they welcomed
          the signs of spring" [syn: {mark}]
     2: a public display of a (usually written) message; "he posted
        signs in all the shop windows"
     3: any communication that encodes a message; "signals from the
        boat suddenly stopped" [syn: {signal}, {signaling}]
     4: structure displaying a board on which advertisements can be
        posted; "the highway was lined with signboards" [syn: {signboard}]
     5: (astrology) one of 12 equal areas into which the zodiac is
        divided [syn: {sign of the zodiac}, {star sign}, {mansion},
         {house}, {planetary house}]
     6: (medicine) any objective evidence of the presence of a
        disorder or disease; "there were no signs of asphixiation"
     7: having an indicated pole (as the distinction between
        positive and negative electric charges); "he got the
        polarity of the battery reversed"; "charges of opposite
        sign" [syn: {polarity}]
     8: an event that is experienced as indicating important things
        to come; "he hoped it was an augury"; "it was a sign from
        God" [syn: {augury}, {foretoken}, {preindication}]
     9: a gesture that is part of a sign language
     10: a fundamental linguistic unit linking a signifier to that
         which is signified; "The bond between the signifier and
         the signified is arbitrary"--de Saussure
     11: a character indicating a relation between quantities; "don't
         forget the minus sign"

sign
     v 1: mark with one's signature; write one's name (on); "She
          signed the letter and sent it off"; "Please sign here"
          [syn: {subscribe}]
     2: approve and express assent, responsibility, or obligation;
        "All parties ratified the peace treaty"; "Have you signed
        your contract yet?" [syn: {ratify}]
     3: be engaged by a written agreement; "He signed to play the
        casino on Dec. 18"; "The soprano signed to sing the new
        opera"
     4: engage by written agreement; "They signed two new pitchers
        for the next season" [syn: {contract}, {sign on}, {sign up}]
     5: communicate silently and non-verbally by signals or signs;
        "He signed his disapproval with a dismissive hand
        gesture"; "The diner signaled the waiters to bring the
        menu" [syn: {signal}, {signalize}, {signalise}]
     6: place signs, as along a road; "sign an intersection"; "This
        road has been signed"
     7: communicate in sign language; "I don't know how to sign, so
        I could not communicate with my deaf cousin"
     8: make the sign of the cross over someone in order to call on
        God for protection; consecrate [syn: {bless}]