### Clue: Excuse me, what did you say?" written back in the morning (4)
### Answer: AHEM 
 ### Explanation: Definition: Excuse me
 **Reversal of**(written back) EH?(a terse way of asking "what did you say?") **contained in**(in) AM(the morning, from "ante meridiem", Latin for "before noon").
Answer: An interjection to attract someone's attention.