Prude is changing list - scandalous (12)
I believe the answer is:
disreputable
'scandalous' is the definition.
(thesaurus)
'prude is changing list' is the wordplay.
'changing' indicates anagramming the letters.
'list' becomes 'table' (list can mean a table or chart).
'prude'+'is'='prudeis'
'prudeis' is an anagram of 'disrepu'.
'disrepu'+'table'='DISREPUTABLE'
(Other definitions for disreputable that I've seen before include "Not of decent character" , "Lacking public estimation" , "Infamous - shabby" , "not proper or decent!" , "Dodgy" .)