A musical country by the sound of it (6)
I believe the answer is:
grease
'a musical' is the definition.
(Grease is a film musical)
'country by the sound of it' is the wordplay.
'country' becomes 'greece' (Greece is a European country).
'by the sound of it' indicates a 'sounds like' (homophone) clue.
'greece' is a homophone of 'GREASE'.
(Other definitions for grease that I've seen before include "A thick oily substance" , "Thick lubricant or frying oil" , "Musical animal fat?" , "Rock musical" , "bribe" .)