Kings are figures of authority and should be addressed with respect. Using such terms trivializes their position and can be considered offensive.
The appropriate way to address a king depends on the specific context and the cultural norms of the country. Some common titles include:
* Your Majesty
* Your Highness
* King [name]
* Sire
It's always best to err on the side of caution and use respectful language when referring to royalty.