Controversial European on microphone (7)
I believe the answer is:
polemic
'controversial' is the definition.
(similar in meaning)
'european on microphone' is the wordplay.
'european' becomes 'pole' (Pole is an example).
'on' means one lot of letters go next to another.
'microphone' becomes 'mic'.
'pole'+'mic'='POLEMIC'
(Other definitions for polemic that I've seen before include "Controversial line of argument" , "harangue" , "Controversial speech or writing" , "Compile to make verbal attack on belief" , "Hostile argument" .)