Marksman notes facial feature (12)
I believe the answer is:
sharpshooter
'marksman' is the definition.
(I know that marksman can be written as sharpshooter)
'notes facial feature' is the wordplay.
'notes' becomes 'sharps' (I've seen this before).
'facial feature' becomes 'hooter' (I am not sure about this - if you are sure you should believe this answer much more).
'sharps'+'hooter'='SHARPSHOOTER'
Can you help me to learn more?
(Other definitions for sharpshooter that I've seen before include "I'm very good at firing" , "Someone with gun" , "skilled marksman" , "Gunman" , "Expert marksman" .)