A&E dressing wound – doctor's stern and more urgently pressing (6)
I believe the answer is:
acuter
'and more urgently pressing' is the definition.
I can't tell whether this defines the answer.
'ae dressing wound doctor's stern' is the wordplay.
'dressing' means one lot of letters goes inside another (inserted letters are dressed or clad in others).
'wound' becomes 'cut' (cut is a kind of wound).
'doctor's stern' becomes 'r' (I can't explain this - if you can you should give a lot more credence to this answer).
'ae' placed around 'cut' is 'acute'.
'acute'+'r'='ACUTER'
Can you help me to learn more?
(Other definitions for acuter that I've seen before include "Sharper" , "More sharp or shrewd" .)