On the way, always keep out of the ditch! (5)
I believe the answer is:
steer
'keep out of the ditch' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'on the way always' is the wordplay.
'on' means one lot of letters go next to another.
'the way' becomes 'st'.
'always' becomes 'eer' (poetic way of saying ever).
'st' next to 'eer' is 'STEER'.
Can you help me to learn more?
(Other definitions for steer that I've seen before include "Manoeuvre" , "give guidance" , "Pilot a boat in desired direction" , "farm animal" , "member of herd" .)