Alarm (5)
'alarm' is the definition.
(I know that siren is a type of alarm)
This is all the clue.
(Other definitions for siren that I've seen before include "Warning device - femme fatale" , "Warning at sea" , "Device producing a loud wailing sound as a signal" , "Loud whistle for sea temptress" , "Risen like Lorelei" .)
'alarm' is the definition.
(alarm can mean panic or worry)
This is all the clue.
(Other definitions for panic that I've seen before include "Greek god" , "Losing one's head" , "Agitation" , "Overwhelming terror" , "Fearful confusion" .)
'alarm' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for alert that I've seen before include "'Attentive, vigilant (5)'" , "Warning signal" , "Intellectually active" , "Vigilant, watchful" , "Watchfully awake" .)
'alarm' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for consternation that I've seen before include "Dismay - cast-iron tenon (anag)" , "Worry" , "Anxiety, dismay" , "Alarm" , "Feelings of dismay" .)
(Other definitions for unnerve that I've seen before include "Cause to lose confidence" , "Psych out" , "Disheartened" , "Make one get in a fluster" , "Faze" .)
'alarm' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for startle that I've seen before include "Take (someone) aback" , "Cause to jump" , "Surprise greatly, alarm" , "Take unawares with rattles" , "Alarm (someone)" .)
'alarm' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for frighten that I've seen before include "Cause fear" , "Put the wind up" , "Terrify" , "Cause alarm" , "Spook" .)
'alarm' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for fear that I've seen before include "Dread, great anxiety" , "Fright" , "Alarm, reverence" , "Apprehension" , "Consternation" .)