Source : Webster's Revised Unabridged Dictionary (1913)

Broadcast \Broad"cast`\, n. (Agric.)
   A casting or throwing seed in all directions, as from the
   hand in sowing.

Broadcast \Broad"cast`\, a.
   1. Cast or dispersed in all directions, as seed from the hand
      in sowing; widely diffused.

   2. Scattering in all directions (as a method of sowing); --
      opposed to planting in hills, or rows.

Broadcast \Broad"cast`\, adv.
   So as to scatter or be scattered in all directions; so as to
   spread widely, as seed from the hand in sowing, or news from
   the press.

Source : WordNet®

broadcast
     n 1: message that is transmitted by radio or television
     2: a radio or television show; "did you see his program last
        night?" [syn: {program}, {programme}]
     v 1: broadcast over the airwaves, as in radio or television; "We
          cannot air this X-rated song" [syn: {air}, {send}, {beam},
           {transmit}]
     2: sow over a wide area, especially by hand; "broadcast seeds"
     3: cause to become widely known; "spread information";
        "circulate a rumor"; "broadcast the news" [syn: {circulate},
         {circularize}, {circularise}, {distribute}, {disseminate},
         {propagate}, {spread}, {diffuse}, {disperse}, {pass
        around}]

Source : Free On-Line Dictionary of Computing

broadcast
     
        A transmission to multiple, unspecified recipients.  On
        Ethernet, a broadcast packet is a special type of multicast
        packet which all nodes on the network are always willing to
        receive.