Pen new melody for deity (7)
I believe the answer is:
neptune
'deity' is the definition.
(Neptune is an example)
'pen new melody' is the wordplay.
'new' indicates anagramming the letters.
'melody' becomes 'tune' (synonyms).
'pen' with letters rearranged gives 'nep'.
'nep'+'tune'='NEPTUNE'
'for' acts as a link.
(Other definitions for neptune that I've seen before include "King of the sea" , "heavenly body" , "one of the Planets" , "Planet, identified 1846" , "Eighth rock from the Sun" .)