Published letters for remote district (7)
I believe the answer is:
outpost
'remote district' is the definition.
The answer and definition can be both locations as well as being singular nouns.
Maybe there's an association between them I don't understand?
'published letters' is the wordplay.
'published' becomes 'out' (a published book is 'out').
'letters' becomes 'post' (letters in the mail or post).
'out'+'post'='OUTPOST'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for outpost that I've seen before include "Distant station or branch" , "isolated settlement" , "distant location" , "Small camp some distance away from the main army" , "settlement far off" .)