noun
signal flare; fusee
A pyrotechnic device used for signaling, especially in railway or maritime contexts. The term is technical and not commonly used in everyday conversation.
鉄道員は緊急時に信号炎管を使用する。
Railway workers use signal flares in emergencies.
信号炎管は赤い炎を上げて危険を知らせる。
A signal flare emits a red flame to warn of danger.
Compound of 信号 (signal) + 炎 (flame) + 管 (tube). The term likely originated in railway or maritime safety contexts.