信号火 meaning in Chinese

pyrotechnic light

Now they approached the darker smudge that had been the signal fire, yawning, rubbing their eyes, treading with practised feet .
这会儿他们走近曾经是信号火的一堆黑漆漆的余烬，打着呵欠，揉着眼睛，熟门熟路地走着。
The signal fire ' s probably out
信号火大概熄灭了
A colored flare used as a warning signal for trucks and railroad trains
信号火一种为卡车或火车作警告信号的有色火焰