Quiet rite involved money (8)
I believe the answer is:
reticent
'quiet' is the definition.
(thesaurus)
'rite involved money' is the wordplay.
'involved' indicates anagramming the letters.
'money' becomes 'cent' (I've seen this before).
'rite' with letters rearranged gives 'reti'.
'reti'+'cent'='RETICENT'
(Other definitions for reticent that I've seen before include "Secretive" , "Reserved, not revealing thoughts readily" , "Close-lipped" , "Reserved, loath to talk" , "Not forthcoming" .)