One page on pop singer that's heard through the grapevine (6)
I believe the answer is:
gossip
'the grapevine' is the definition.
(thesaurus)
'one page on pop singer' is the wordplay.
'one' becomes 'i' (Roman numeral).
'page' becomes 'p'.
'on' says to put letters next to each other.
'pop singer' becomes 'goss' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'i'+'p'='ip'
'ip' put after 'goss' is 'GOSSIP'.
'that's heard through' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for gossip that I've seen before include "Tittle-tattle" , "Idle talk and rumour" , "Casual inaccurate talk about others" , "Rabbit" , "Busybody" .)