Austrian composer Berg (5)
I believe the answer is:
alban
'austrian composer berg' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for alban that I've seen before include "early martyr" , "First English Christian martyr" , "Saint born at Verulamium" , "First Christian martyr in England" , "Saintly type" .)