Horribly garbled English in European capital (8)
I believe the answer is:
belgrade
'european capital' is the definition.
(capital of Serbia)
'horribly garbled english in' is the wordplay.
'horribly' indicates anagramming the letters (a horribly wrong version of the letters).
'english' becomes 'E' (abbreviation).
'in' means one lot of letters goes inside another.
'garbled' is an anagram of 'blgrade'.
'blgrade' enclosing 'e' is 'BELGRADE'.
(Other definitions for belgrade that I've seen before include "Foreign capital" , "Serbian city" , "Capital of former Yugoslavia" , "Capital of Serbia and Montenegro" , "Capital city - large bed (anag)" .)