The simultaneous transmission of data to several destinations on a network(noun)
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Use "multicasting" in a sentence
"But DTV also allows a broadcaster to transmit more than one show on a channel, called multicasting."
"HD Tranny technology also makes possible something called multicasting that allows stations to broadcast two or more several signals simultaneously."
"DTV makes it possible for stations to broadcast in high definition or provide multiple channels of programming simultaneously (called multicasting), instead of broadcasting only onechannel at a time."