He puts an end to some central asian countries (4)
I believe the answer is:
stan
'he' is the definition.
'an end to some central asian countries' is the wordplay.
'an end to' becomes 'st' (I can't explain this - if you can you should believe this answer much more).
'some central' indicates the central letters.
'asian countries' becomes 'Lebanons' (Lebanon is an example).
The middle of 'lebanons' is 'an'.
'st'+'an'='STAN'
'puts' acts as a link.
Can you help me to learn more?
(Other definitions for stan that I've seen before include "- Getz, jazz musician" , "Laurel perhaps" , "Laurel and Hardy, . . . . and Ollie" , "One of the comic duo" , "Eminem hit; man's name" .)