CEDICT
alarm; warning; alert
Wiktionary
對可能或即將來臨的危急事件所作的警戒報訊。
重編國語辭典
對可能或即將來臨的危急事件所作的警戒信號
維基詞典
The fire alarm rang.
Source: Tatoeba
The tsunami alert was cancelled.
This was a warning: the floods were coming.
This startled me.