Source : Webster's Revised Unabridged Dictionary (1913)

Trade \Trade\, v. i. [imp. & p. p. {Traded}; p. pr. & vb. n.
   {Trading}.]
   1. To barter, or to buy and sell; to be engaged in the
      exchange, purchase, or sale of goods, wares, merchandise,
      or anything else; to traffic; to bargain; to carry on
      commerce as a business.

            A free port, where nations . . . resorted with their
            goods and traded.                     --Arbuthnot.

   2. To buy and sell or exchange property in a single instance.

   3. To have dealings; to be concerned or associated; --
      usually followed by with.

            How did you dare to trade and traffic with Macbeth?
                                                  --Shak.

Trading \Trad"ing\, a.
   1. Carrying on trade or commerce; engaged in trade; as, a
      trading company.

   2. Frequented by traders. [R.] ``They on the trading flood.''
      --Milton.

   3. Venal; corrupt; jobbing; as, a trading politician.

Source : WordNet®

trading
     n : buying or selling securities or commodities