Serious doctor absorbed by wound? (6)
I believe the answer is:
sombre
'serious' is the definition.
(I've seen this before)
'doctor absorbed by wound?' is the wordplay.
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'absorbed by' means one lot of letters goes inside another.
'wound?' becomes 'sore' (I've seen this before).
'mb' put inside 'sore' is 'SOMBRE'.
(Other definitions for sombre that I've seen before include "Grey" , "Grave and serious" , "Lugubrious" , "Dark, dull" , "Dull, gloomy" .)