longest nerve in the body (7)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
sciatic
(Other definitions for sciatic that I've seen before include "Relating to the hip or to pain around the body's longest nerve" , "Nerve connected with back pain" , "(Of a nerve) in the region of the hip" , "Relating to a nerve of the lower back" , "Largest nerve in the body" .)