Quietly checks back about concealed danger (6)
I believe the answer is:
sniper
'concealed danger' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'quietly checks back about' is the wordplay.
'quietly' becomes 'p' (p for piano and quiet).
'checks' becomes 'reins' (reining is a kind of checking).
'back' shows that the letters should be reversed in order.
'about' means one lot of letters goes inside another.
'reins' written backwards gives 'snier'.
'p' put into 'snier' is 'SNIPER'.
Can you help me to learn more?
(Other definitions for sniper that I've seen before include "Critic" , "One who criticises" , "Concealed sharpshooter" , "Individual firing from cover" , "Rifleman firing from concealed location" .)