Guide soldiers over Dartmoor landmark? (6)
I believe the answer is:
mentor
'guide' is the definition.
(I've seen this before)
'soldiers over dartmoor landmark?' is the wordplay.
'soldiers' becomes 'men' (I've seen this before).
'over' means one lot of letters go next to another.
'dartmoor landmark?' becomes 'tor' (type of rocky hill - Dartmoor has many of them).
'men'+'tor'='MENTOR'
(Other definitions for mentor that I've seen before include "A wise and experienced teacher" , "Somebody advising" , "One who steers" , "A wise and learned teacher" , "Wise and experienced counsellor" .)