Melodious harp one played (7)
I believe the answer is:
orphean
'melodious' is the definition.
(I've seen this before)
'harp one played' is the wordplay.
'played' indicates anagramming the letters (letters playing around).
'harp'+'one'='harpone'
'harpone' is an anagram of 'ORPHEAN'.
(Other definitions for orphean that I've seen before include "Enchanting" , "Melodious" , "Pertaining to mythical lyre player" , "of legendary musician" .)