Sentence:  There goes the <WSD>siren</WSD> that warns of the air raid / Then comes the sound of the guns sending flak / Out for the scramble we've got to get airborne / Got to get up for the coming attack. 
Meaning of the word marked with <WSD> tags:  A device, either mechanical or electronic, that makes a piercingly loud sound as an alarm or signal, or the sound from such a device (first recorded 1879).