The right to enter a particular sphere (6)
I believe the answer is:
entree
'the right to enter a particular sphere' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for entree that I've seen before include "Dish; right of admission" , "Right of entrance for a dish?" , "part of meal" , "Principal dish and right to enter" , "Something that provides access" .)