Had spread rumour about attachment (8)
I believe the answer is:
adhesion
'attachment' is the definition.
(thesaurus)
'had spread rumour about' is the wordplay.
'spread' is an anagram indicator.
'rumour' becomes 'noise' (I've seen this before).
'about' says the letters should be written backwards.
'noise' written backwards gives 'esion'.
'had' is an anagram of 'adh'.
'adh'+'esion'='ADHESION'
(Other definitions for adhesion that I've seen before include "Adonis, he may be a sticker" , "strong attachment" , "steady attachment" , "Process of sticking together" , "Sticking fast" .)