Nobleman almost loses case (4)
I believe the answer is:
earl
'nobleman' is the definition.
(member of the nobility)
'almost loses case' is the wordplay.
'almost' becomes 'nearly' (synonyms).
'loses case' means to look at the middle letters (the case is the outside letters).
The middle of 'nearly' is 'EARL'.
(Other definitions for earl that I've seen before include "-- Grey, PM 1830-34" , "Titled man" , "A real sort of lord" , "Male member of British nobility" , "Peer of the realm" .)