Melodic lute, fun to play (7)
I believe the answer is:
tuneful
'melodic' is the definition.
(I've seen this before)
'lute fun to play' is the wordplay.
'to play' indicates an anagram.
'lute'+'fun'='lutefun'
'lutefun' anagrammed gives 'TUNEFUL'.
(Other definitions for tuneful that I've seen before include "Melodic" , "With a pleasing musical sound" , "Harmonious" , "Euphonious" , "Euphonic" .)