Source : Webster's Revised Unabridged Dictionary (1913)

Barter \Bar"ter\, v. i. [imp. & p. p. {Bartered} (?); p. pr. &
   vb. n. {Bartering}.] [OE. bartren, OF. barater, bareter, to
   cheat, exchange, perh. fr. Gr. ? to do, deal (well or ill),
   use practices or tricks, or perh. fr. Celtic; cf. Ir. brath
   treachery, W. brad. Cf. {Barrator}.]
   To traffic or trade, by exchanging one commodity for another,
   in distinction from a sale and purchase, in which money is
   paid for the commodities transferred; to truck.

Barter \Bar"ter\, v. t.
   To trade or exchange in the way of barter; to exchange
   (frequently for an unworthy consideration); to traffic; to
   truck; -- sometimes followed by away; as, to barter away
   goods or honor.

Barter \Bar"ter\, n.
   1. The act or practice of trafficking by exchange of
      commodities; an exchange of goods.

            The spirit of huckstering and barter. --Burke.

   2. The thing given in exchange.

   Syn: Exchange; dealing; traffic; trade; truck.

Source : WordNet®

barter
     n : an equal exchange; "we had no money so we had to live by
         barter" [syn: {swap}, {swop}, {trade}]
     v : exchange goods without involving money