### Clue: Roman emperor, regularly ignoring advisor, called time on Scotsman (10)
### Answer: DIOCLETIAN 
 ### Explanation: Definition: Roman emperor
 **The 1st letter, and thereafter every other letter deleted from**(regularly ignoring) "advisor, called" + T(abbrev. for "time") **placed above**(on, in a down clue) IAN(a popular name among male Scots, the equivalent of John).