Merriment with one scoundrel around city railway (9)
I believe the answer is:
funicular
'railway' is the definition.
(funicular railway is a kind of railway)
'merriment with one scoundrel around city' is the wordplay.
I cannot quite see how this works, but
'merriment' could be 'fun' (synonyms) and 'fun' is present in the answer.
'one' could be 'i' (Roman numeral) and 'i' is located in the answer.
'around' could be 'c' (abbreviation for 'circa') and 'c' is found in the answer.
'city' could be 'la' (Los Angeles) and 'la' is located in the answer.
The remaining letters 'ur' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for funicular that I've seen before include "Using a cable" , "Railway up the side of a mountain" , "Cable railway" , "(Of a railway) cable-operated" .)