The Collaborative International Dictionary of English v.0.48:

Boast \Boast\, v. t.
   1. To display in ostentatious language; to speak of with
      pride, vanity, or exultation, with a view to
      self-commendation; to extol.
      [1913 Webster]

            Lest bad men should boast
            Their specious deeds.                 --Milton.
      [1913 Webster]

   2. To display vaingloriously.
      [1913 Webster]

   3. To possess or have; as, to boast a name.
      [1913 Webster]

   To boast one's self, to speak with unbecoming confidence
      in, and approval of, one's self; -- followed by of and the
      thing to which the boasting relates. [Archaic]
      [1913 Webster]

            Boast not thyself of to-morrow.       --Prov. xxvii.
                                                  1
      [1913 Webster]