Department of a French cross-country runner (5)
I believe the answer is:
isere
This might be a double definition.
'department' is the first definition.
(I have seen 'French department' mean 'isere' so perhaps 'department' could also mean 'isere')
'french cross-country runner' is the second definition.
'isere' can be an answer for 'runner' (I have seen 'French runner' mean 'isere' so perhaps 'runner' could also mean 'isere'). I am unsure of the 'french cross-country' bit.
'of a' is the link.
Can you help me to learn more?
(Other definitions for isere that I've seen before include "French division" , "part of France" , "River and department of southeast France" , "French department" , "River of south-eastern France" .)