Song line recalled rumour about island (5)
I believe the answer is:
lyric
'song' is the definition.
(thesaurus)
'line recalled rumour about island' is the wordplay.
'line' becomes 'l'.
'recalled' says the letters should be written in reverse.
'rumour' becomes 'cry'.
'about' means one lot of letters goes inside another.
'island' becomes 'i'.
'cry' going around 'i' is 'ciry'.
'ciry' written backwards gives 'yric'.
'l'+'yric'='LYRIC'
(Other definitions for lyric that I've seen before include "Part of a libretto" , "Poem - verse - London theatre" , "part of song" , "Text of a popular song" , "having a light quality" .)