Station American in establishment near Slough (6)
I believe the answer is:
euston
'station' is the definition.
(London train station)
'american in establishment near slough' is the wordplay.
I cannot quite see how this works, but
'american' could be 'us' (United States) and 'us' is found within the answer.
'near' could be 'to' (to can mean near or close to) and 'to' is located in the answer.
The remaining letters 'en' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for euston that I've seen before include "north London area" , "train here?" , "London mainline station" , "No suet (anag)" , "London railway station" .)