Learn how to say Multicasting correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word multicast:
verb (past and past participle multicast)
send (data) across a computer network to several users at the same time:
the circuits can multicast data streams
an Internet radio station has been multicasting for more than a year
a set of data sent across a computer network to many users at the same time:
live multicasts of events at the National Press Club