Matter to aristocrat (5)
I believe the answer is:
count
I believe this is a double definition.
'matter' is the first definition.
(both can mean to be of significance)
'to aristocrat' is the second definition.
(some European aristocracies have counts)
(Other definitions for count that I've seen before include "Nobleman - enumerate" , "earl abroad" , "regard" , "twenty three [NOBLE] from abroad" , "Total" .)