Students of French enthralled by derrires (7)
I believe the answer is:
readers
'students' is the definition.
(reader is a kind of student)
'of french enthralled by derrires' is the wordplay.
'of french' becomes 'de' ('of' in French).
'enthralled by' means one lot of letters goes inside another ('enthral' can mean 'capture').
'derrires' becomes 'rears' (I am not sure about this - if you are sure you should believe this answer much more).
'de' inserted inside 'rears' is 'READERS'.
Can you help me to learn more?
(Other definitions for readers that I've seen before include "Student textbooks" , "Senior lecturers" , "Consumers of the written word" , "cheaters" , "Checkers of proofs" .)