Warden aggravated the cross nominee for Scotland (6)
I believe the answer is:
andrew
'cross nominee for scotland' is the definition.
(as in St Andrew's cross, flag of Scotland)
'warden aggravated' is the wordplay.
'aggravated' indicates anagramming the letters.
'warden' anagrammed gives 'ANDREW'.
'the' acts as a link.
(Other definitions for andrew that I've seen before include "Nov thirtieth this saint's day" , "Peter's brother" , "- - Marr (TV)" , "apostle" , "Warden (anag.)" .)