NICAM is a system British television companies used to broadcast sound in stereo — so the sound could come from two sides, like music on a decent stereo, instead of a single thin voice from the middle of the set. It belonged to the analogue TV age, when pictures came over the air in the old way, before digital boxes and streaming. The letters stand for Near Instantaneous Companded Audio Multiplex; nobody says that in ordinary life. Though actually, you almost never hear NICAM now unless someone is talking about old televisions or how broadcasts used to work. A “NICAM stereo” badge on a TV was once a selling point, the way HD was later. Digital TV replaced it.

麗音（類比電視的立體聲系統；英國寫 NICAM）