Some seriously rich singer's text (5)
I believe the answer is:
lyric
'text' is the definition.
(lyric is a kind of text)
'some seriously rich singer's' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'LYRIC' is hidden in the letters of 'seriously rich singer'.
(Other definitions for lyric that I've seen before include "Expressing poetical emotions" , "(Of poetry) expressing emotion" , "something to sing about? On the contrary" , "Type of poem" , "Expressing personal feelings" .)