Source : Webster's Revised Unabridged Dictionary (1913)

Unite \U*nite"\, a. [L. unitus, p. p. See {Unite}, v. t.]
   United; joint; as, unite consent. [Obs.] --J. Webster.

Unite \U*nite"\, v. t. [imp. & p. p. {United}; p. pr. & vb. n.
   {Uniting}.] [L. unitus, p. p. of unire to unite, from unus
   one. See {One}.]
   1. To put together so as to make one; to join, as two or more
      constituents, to form a whole; to combine; to connect; to
      join; to cause to adhere; as, to unite bricks by mortar;
      to unite iron bars by welding; to unite two armies.

   2. Hence, to join by a legal or moral bond, as families by
      marriage, nations by treaty, men by opinions; to join in
      interest, affection, fellowship, or the like; to cause to
      agree; to harmonize; to associate; to attach.

            Under his great vicegerent reign abide, United as
            one individual soul.                  --Milton.

            The king proposed nothing more than to unite his
            kingdom in one form of worship.       --Clarendon.

   Syn: To add; join; annex; attach. See {Add}.

Unite \U*nite"\, v. i.
   1. To become one; to be cemented or consolidated; to combine,
      as by adhesion or mixture; to coalesce; to grow together.

   2. To join in an act; to concur; to act in concert; as, all
      parties united in signing the petition.

Source : WordNet®

unite
     v 1: act in concert or unite in a common purpose or belief [syn:
          {unify}] [ant: {divide}]
     2: become one; "Germany unified officially in 1990"; "Will the
        two Koreas unify?" [syn: {unify}, {merge}] [ant: {disunify}]
     3: have or possess in combination; "she unites charm with a
        good business sense" [syn: {combine}]
     4: 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}, {join}]
     5: join or combine; "We merged our resources" [syn: {unify}, {merge}]