German, but he has a British car (4)
I believe the answer is:
herr
'german' is the definition.
(German equivalent to Mr)
'he has a british car' is the wordplay.
'has' means one lot of letters go next to another.
'a british car' becomes 'rr' (Rolls Royce. I am not sure about the 'british' bit.).
'he'+'rr'='HERR'
'but' is the link.
Can you help me to learn more?
(Other definitions for herr that I've seen before include "Mister in German" , "German form like Mr." , "A German gentleman" , "Dieter respectfully addressed" , "German man's title" .)