### Clue: Bill has upset French king? The American ass! (9)
### Answer: POSTERIOR 
 ### Explanation: Definition: ass
  POSTER(*bill*,a poster usually advertising some coming event, could be handed out, or pasted on to a wall or post.  I remember the irony of posters on walls, which posters said "Post No Bills") + reversal(upset) of ROI(*French* word for *king*).
Defn:  The Commonwealth calls it arse, while the *American*s *ass* (homophonic euphemism?).  Speaking of which, I always thought that Madras (in the verses below) rhymes with the Commonwealth version.
There was an Old Man of Madras
Who rode on a cream-coloured ass
But the length of its ears
So promoted his fears
That it killed that Old Man of Madras
– Edward Lear
There was a young girl from Madras
Who had a most beautiful ass
Not rounded and pink
As you probably think
But gray, with long ears, and ate grass
– Anon, after Lear.