Nobility of servant protecting English Queen (7)
I believe the answer is:
peerage
'nobility' is the definition.
(peerage is a kind of nobility)
'servant protecting english queen' is the wordplay.
'servant' becomes 'page' (I've seen this before).
'protecting' is an insertion indicator.
'english' becomes 'e' (abbreviation).
'queen' becomes 'er' (abbreviation for Elizabeth Regina).
'e'+'er'='eer'
'page' enclosing 'eer' is 'PEERAGE'.
'of' acts as a link.
(Other definitions for peerage that I've seen before include "Book of the nobility" , "Lordly group" , "Listing of the nobility (eg, Burke's)" , "Ranks of the nobility" , "The nobility as a group" .)