Definitions

1. noun

An American mass media conglomerate that was formed in 2005 as a spin-off from the original Viacom, which was founded by Sumner Redstone in 1971.

“The acquisition of CBS by Viacom marked a significant shift in the media landscape.”

2. proper noun

A former American media conglomerate that existed from 1952 to 2006, and was a major division of CBS Corporation.

“The original Viacom was founded by Wilfred R. Rice and Fred R. McCormick.”