Hill test for vehicle crossing French one (5)
I believe the answer is:
mount
'hill' is the definition.
(I've seen this before)
'test for vehicle crossing french one' is the wordplay.
I cannot quite see how this works, but
'one' could be 'un' (northern English dialect form of 'one') and 'un' is present in the answer.
'test' could be 'mot' (MOT test) and 'mot' is present in the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for mount that I've seen before include "put on launch" , "Produce - horse" , "stage" , "The height" , "Fix onto a backing" .)