Source : Webster's Revised Unabridged Dictionary (1913)

One \One\, a. [OE. one, on, an, AS. ["a]n; akin to D. een, OS.
   ["e]n, OFries. ["e]n, ["a]n, G. ein, Dan. een, Sw. en, Icel.
   einn, Goth. ains, W. un, Ir. & Gael. aon, L. unus, earlier
   oinos, oenos, Gr. ? the ace on dice; cf. Skr. ["e]ka. The
   same word as the indefinite article a, an. [root] 299. Cf. 2d
   A, 1st {An}, {Alone}, {Anon}, {Any}, {None}, {Nonce}, {Only},
   {Onion}, {Unit}.]
   1. Being a single unit, or entire being or thing, and no
      more; not multifold; single; individual.

            The dream of Pharaoh is one.          --Gen. xli.
                                                  25.

            O that we now had here But one ten thousand of those
            men in England.                       --Shak.

   2. Denoting a person or thing conceived or spoken of
      indefinitely; a certain. ``I am the sister of one
      Claudio'' [--Shak.], that is, of a certain man named
      Claudio.

   3. Pointing out a contrast, or denoting a particular thing or
      person different from some other specified; -- used as a
      correlative adjective, with or without the.

            From the one side of heaven unto the other. --Deut.
                                                  iv. 32.

   4. Closely bound together; undivided; united; constituting a
      whole.

            The church is therefore one, though the members may
            be many.                              --Bp. Pearson

   5. Single in kind; the same; a common.

            One plague was on you all, and on your lords. --1
                                                  Sam. vi. 4.

   6. Single; inmarried. [Obs.]

            Men may counsel a woman to be one.    --Chaucer.

   Note: One is often used in forming compound words, the
         meaning of which is obvious; as, one-armed, one-celled,
         one-eyed, one-handed, one-hearted, one-horned,
         one-idead, one-leaved, one-masted, one-ribbed,
         one-story, one-syllable, one-stringed, one-winged, etc.

   {All one}, of the same or equal nature, or consequence; as,
      he says that it is all one what course you take. --Shak.

One \One\, n.
   1. A single unit; as, one is the base of all numbers.

   2. A symbol representing a unit, as 1, or i.

   3. A single person or thing. ``The shining ones.'' --Bunyan.
      ``Hence, with your little ones.'' --Shak.

            He will hate the one, and love the other. --Matt.
                                                  vi. 24.

            That we may sit, one on thy right hand, and the
            other on thy left hand, in thy glory. --Mark x. 37.

   {After one}, after one fashion; alike. [Obs.] --Chaucer.

   {At one}, in agreement or concord. See {At one}, in the
      Vocab.

   {Ever in one}, continually; perpetually; always. [Obs.]
      --Chaucer.

   {In one}, in union; in a single whole.

   {One and one}, {One by one}, singly; one at a time; one after
      another. ``Raising one by one the suppliant crew.''
      --Dryden.

One \One\, v. t.
   To cause to become one; to gather into a single whole; to
   unite; to assimilite. [Obs.]

         The rich folk that embraced and oned all their heart to
         treasure of the world.                   --Chaucer.

One \One\, indef. pron.
   Any person, indefinitely; a person or body; as, what one
   would have well done, one should do one's self.

         It was well worth one's while.           --Hawthorne.

         Against this sort of condemnation one must steel one's
         self as one best can.                    --G. Eliot.

   Note: One is often used with some, any, no, each, every,
         such, a, many a, another, the other, etc. It is
         sometimes joined with another, to denote a reciprocal
         relation.

               When any one heareth the word.     --Matt. xiii.
                                                  19.

               She knew every one who was any one in the land of
               Bohemia.                           --Compton
                                                  Reade.

               The Peloponnesians and the Athenians fought
               against one another.               --Jowett
                                                  (Thucyd. ).

               The gentry received one another.   --Thackeray.

Source : WordNet®

one
     adj 1: used of a single unit or thing; not two or more; "`ane' is
            Scottish" [syn: {1}, {i}, {ane}]
     2: particular but unspecified; "early one evening" [syn: {one(a)}]
     3: having the indivisible character of a unit; "a unitary
        action"; "spoke with one voice" [syn: {one(a)}, {unitary}]
     4: of the same kind or quality; "two animals of one species"
        [syn: {one(a)}]
     5: used informally as an intensifier; "that is one fine dog"
        [syn: {one(a)}]
     6: indefinite in time or position; "he will come one day"; "one
        place or another" [syn: {one(a)}]
     7: being the single appropriate individual of a kind; only;
        "the one horse that could win this race"; "the one person
        I could marry" [syn: {one(a)}]
     8: being one in number--a single unit or thing; "one person is
        going"; "her one thought was to win"; "I'm just one player
        on the team"; "one day is just like the next"; "seen one
        horse and you've seen them all" [syn: {one(a)}]
     9: being a single entity made by combining separate components;
        "three chemicals combining into one solution"
     10: eminent beyond or above comparison; "matchless beauty"; "the
         team's nonpareil center fielder"; "she's one girl in a
         million"; "the one and only Muhammad Ali"; "a peerless
         scholar"; "infamy unmatched in the Western world"; "wrote
         with unmatchable clarity"; "unrivaled mastery of her art"
         [syn: {matchless}, {nonpareil}, {one(a)}, {one and
         only(a)}, {peerless}, {unmatched}, {unmatchable}, {unrivaled},
          {unrivalled}]

one
     n 1: the smallest whole number or a numeral representing this
          number; "he has the one but will need a two and three to
          go with it"; "they had lunch at one" [syn: {1}, {I}, {ace},
           {single}, {unity}]
     2: a single person or thing; "he is the best one"; "this is the
        one I ordered"