Alarm seeming loud to a listener (4)
I believe the answer is:
fear
'alarm seeming' is the definition.
'fear' can be an answer for 'alarm' (I've seen this before). I am not certain of the 'seeming' bit.
'loud to a listener' is the wordplay.
'loud' becomes 'f' (short for forte - 'loud' in music).
'to a listener' becomes 'ear' (body part which hears or listens).
'f'+'ear'='FEAR'
Can you help me to learn more?
(Other definitions for fear that I've seen before include "Cutting edge" , "Anxiety caused by danger" , "Be afraid of" , "Dread, great anxiety" , "Fright" .)