Bill in America loves Prohibition (5)
I believe the answer is:
taboo
'prohibition' is the definition.
(thesaurus)
'bill in america loves' is the wordplay.
'bill in america' becomes 'tab' (american english for the bill at end of meal say).
'loves' becomes 'oo'.
'tab'+'oo'='TABOO'
(Other definitions for taboo that I've seen before include "Subject to prohibition" , "Strictly forbidden" , "Inhibition based on social custom" , "Not allowed, forbidden, proscribed" , "unacceptable" .)