One spotted at the station? (5)
I believe the answer is:
train
'station?' is the definition.
(train station is a kind of station)
'one spotted at the' is the wordplay.
'one spotted' becomes 'rain' (I can't justify this - if you can you should believe this answer much more).
'at' says to put letters next to each other (I've seen this in other clues).
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'rain' after 't' is 'TRAIN'.
Can you help me to learn more?
(Other definitions for train that I've seen before include "Learn a skill etc. through practice" , "Succession of carriages" , "Engine and carriages" , "Rail service" , "See 19" .)