Source : Webster's Revised Unabridged Dictionary (1913)

Join \Join\ (join), v. t. [imp. & p. p. {Joined}; p. pr. & vb.
   n. {Joining}.] [OE. joinen, joignen, F. joindre, fr. L.
   jungere to yoke, bind together, join; akin to jugum yoke. See
   {Yoke}, and cf. {Conjugal}, {Junction}, {Junta}.]
   1. To bring together, literally or figuratively; to place in
      contact; to connect; to couple; to unite; to combine; to
      associate; to add; to append.

            Woe unto them that join house to house. --Is. v. 8.

            Held up his left hand, which did flame and burn Like
            twenty torches joined.                --Shak.

            Thy tuneful voice with numbers join.  --Dryden.

   2. To associate one's self to; to be or become connected
      with; to league one's self with; to unite with; as, to
      join a party; to join the church.

            We jointly now to join no other head. --Dryden.

   3. To unite in marriage.

            He that joineth his virgin in matrimony. --Wyclif.

            What, therefore, God hath joined together, let not
            man put asunder.                      --Matt. xix.
                                                  6.

   4. To enjoin upon; to command. [Obs. & R.]

            They join them penance, as they call it. --Tyndale.

   5. To accept, or engage in, as a contest; as, to join
      encounter, battle, issue. --Milton.

   {To join battle}, {To join issue}. See under {Battle},
      {Issue}.

   Syn: To add; annex; unite; connect; combine; consociate;
        couple; link; append. See {Add}.

Join \Join\, v. i.
   To be contiguous, close, or in contact; to come together; to
   unite; to mingle; to form a union; as, the hones of the skull
   join; two rivers join.

         Whose house joined hard to the synagogue. --Acts xviii.
                                                  7.

         Should we again break thy commandments, and join in
         affinity with the people of these abominations? --Ezra
                                                  ix. 14.

         Nature and fortune joined to make thee great. --Shak.

Join \Join\, n. (Geom.)
   The line joining two points; the point common to two
   intersecting lines. --Henrici.

Source : WordNet®

join
     n 1: the shape or manner in which things come together and a
          connection is made [syn: {articulation}, {joint}, {juncture},
           {junction}]
     2: a set containing all and only the members of two or more
        given sets; "let C be the union of the sets A and B" [syn:
         {union}, {sum}]

join
     v 1: become part of; become a member of a group or organization;
          "He joined the Communist Party as a young man" [syn: {fall
          in}, {get together}]
     2: cause to become joined or linked; "join these two parts so
        that they fit together" [syn: {bring together}] [ant: {disjoin}]
     3: come into the company of; "She joined him for a drink"
     4: make contact or come together; "The two roads join here"
        [syn: {conjoin}] [ant: {disjoin}]
     5: be or become joined or united or linked; "The two streets
        connect to become a highway"; "Our paths joined"; "The
        travelers linked up again at the airport" [syn: {connect},
         {link}, {link up}, {unite}]

Source : Free On-Line Dictionary of Computing

join
     
        1.  {inner join} (common) or {outer join} (less
        common).
     
        2.  {least upper bound}.
     
        (1998-11-23)