A noble matter (5)
I believe the answer is:
count
I believe this clue is a double definition.
'a noble' is the first definition.
(count is a kind of noble)
'matter' is the second definition.
(Other definitions for count that I've seen before include "Have significance" , "Noble - judge" , "twenty three [NOBLE] from abroad" , "Add up" , "earl abroad" .)