A European gets stuffed by British athlete (7)
I believe the answer is:
acrobat
'athlete' is the definition.
(acrobat is a kind of athlete)
'a european gets stuffed by british' is the wordplay.
'european' becomes 'croat' (I've seen this before).
'gets' is an insertion indicator (gets can mean captures or absorbs).
'stuffed by british' becomes 'b' (I can't justify this - if you can you should give a lot more credence to this answer).
'croat' placed around 'b' is 'crobat'.
'a'+'crobat'='ACROBAT'
(Other definitions for acrobat that I've seen before include "Circus gymnast" , "circus artiste" , "Gymnastic performer" , "Performing gymnast" , "User of five ac" .)