Battlefield ditch
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
trench
'battlefield ditch' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for trench that I've seen before include "Fish; move on ice" , "Deeply cut" , "Long narrow ditch" , "deep channel" , "depression" .)