Arab one after beaten enemy (6)
I believe the answer is:
yemeni
'arab' is the definition.
(I know that Yemeni is a type of arab)
'one after beaten enemy' is the wordplay.
'one' becomes 'i' (Roman numeral).
'after' means one lot of letters go next to another.
'beaten' indicates anagramming the letters (letters beaten up or destroyed).
'enemy' is an anagram of 'yemen'.
'i' after 'yemen' is 'YEMENI'.
(Other definitions for yemeni that I've seen before include "from the Middle East" , "Eg, native of Sana'a" , "from an Arab country" , "Someone from Aden?" , "Native of Sana'a, say" .)