High ground dropped away (4)
I believe the answer is:
fell
This clue could be a double definition.
'high ground' is the first definition.
'fell' can be an answer for 'ground' (thesaurus). I'm unsure of the 'high' bit.
'dropped away' is the second definition.
'fell' can be an answer for 'dropped' (I've seen this before). I'm not sure about the 'away' bit.
Can you help me to learn more?
(Other definitions for fell that I've seen before include "Destructive; a hill" , "Knock down - or was knocked down?" , "Abated" , "Keeled over" , "northern mountain" .)