### Clue: Bum", "fart", "poo" in an act of irreverence (11)
### Answer: PROFANATION 
 ### Explanation: Definition: act of irreverence
 **Anagram of**(Bum)"FART", "POO" IN AN. Well-constructed clue, mentioning 3 words, each of which is, or can be used in, an act of irreverence.