Rank above viscount (4)
I believe the answer is:
earl
'rank above viscount' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for earl that I've seen before include "Peer of the realm" , "... Grey, fragrant Oriental tea" , "Count" , "Rank immediately above viscount" , "Real kind of English lord" .)