This is the 3227th most frequent Swedish word.
siren
A "siren" in Swedish refers to a warning signal device that emits loud sounds to alert or warn.
In this sentence, 'siren' is used to refer to the audible warning signal produced by emergency vehicles.
Brandbilarna körde snabbt genom staden med sirenerna på.
The fire trucks drove quickly through the city with the sirens on.
Here, 'siren' indicates a device used to emit a loud sound for warning purposes in maritime situations.
Sjöräddningen använder sirener för att uppmärksamma båtar om fara.
The sea rescue uses sirens to alert boats of danger.
In this context, 'sirens' refers to mythical creatures from folklore and literature, not to mechanical warning devices.