Desire, possibly, for public transport (9)
I believe the answer is:
streetcar
'desire' is the definition.
(I have seen 'Desire of Tennessee' mean 'streetcar' so perhaps 'desire' could also mean 'streetcar')
'for public transport' is the wordplay.
'for public' becomes 'street' (I can't explain this - if you can you should give a lot more credence to this answer).
'transport' becomes 'car' (car is a method of transport).
'street'+'car'='STREETCAR'
'possibly' acts as a link.
Can you help me to learn more?
(Other definitions for streetcar that I've seen before include ""Desire" was one" , "Tennessee Williams play 'A . . . . . . . . . Named Desire'" , "US tram (named Desire?)" , "Desire, perhaps" , "public transport?" .)