Nurse or nun (6)
I believe the answer is:
sister
This clue is a double definition.
'nurse' is the first definition.
(I've seen this before)
'nun' is the second definition.
(I know that nun can be written as sister)
(Other definitions for sister that I've seen before include "A relative to resist" , "Senior nurse; relative" , "of the same origin" , "Nun's title" , "Tender" .)