smoke signal

US /ˈsmoʊk ˌsɪɡ.nəl/
UK /ˈsmoʊk ˌsɪɡ.nəl/
"smoke signal" picture
1.

烟雾信号

a column of smoke used as a signal, especially one made by a fire on a mountain or hill to send a message

:
The stranded hikers sent up a smoke signal to alert rescuers.
被困的徒步旅行者发出烟雾信号以提醒救援人员。
In ancient times, smoke signals were a common way to communicate over long distances.
在古代,烟雾信号是远距离通信的常用方式。