Jimmy Carter's middle name (4)
I believe the answer is:
earl
'jimmy carter's middle name' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for earl that I've seen before include "Rank below marquess" , "Lear (anag)" , "Countess his wife" , "British peer and Dublin street" , "A real peer" .)