死 氣，即指死了的氣，不再進行"布朗運動"的氣體。死了的氣，一般人吸入會立時感到身體不適，頭暈眼花、腹瀉肚疴、呼吸困難、更會關菊英上身(即是講不出聲 講不出聲)。不信者，可以走近各大汽車後的死氣喉 (Dead Air Pipe)吸一吸死氣，包你死得比一般人快、氣得比一般人氣。
專業一點的解釋如下︰
Dead air is an unintended interruption in a broadcast during which the carrier signal is unmodulated — no sound on a radio signal or a black screen on a television signal.
The term is most often used in cases where programme material comes to an unexpected halt, either through operator error or for technical reasons, although it is also used in cases where a broadcaster has 'dried up'. Among professional broadcasters, dead air is considered one of the worst things that can occur.
