Yes, it is an acceptable title. I suppose that the question comes up because of the master-servant mentality, but "master" is also used in some cases where balance of power isn't an issue. ... the headmaster of a school, for instance. And calling a young person "Master such-and-such is pretty archaic in American English, but in British English it was used frequently in the past, and could be more common even today. So, it probably depends on context. It is acceptable as a grammatically correct form, yes. Appropriate for the situation... it depends. In American English, I would avoid it, using instead just the First and Last name of the young man, and no honorific.
Miss.
MIss
In letter heading you would properly address them as Master So and so.
Master
I think that Master is correct
Master John Doe
Do I address a 5 year old boy as Master when sending him a card.
13-14 years old and a knight at 21.
When addressing an envelope to a boy under 18, you can put Master in front of their name. There are many professions that have master in front of them. You can also address a teacher of certain things as master, especially in Asian arts.
"Señorita" is a Spanish term used to address or refer to a young unmarried woman or girl. If it is used for a boy, it would not have a specific meaning as it is not typically used to address males.
No. Master chief, has no relatives or known parents. He is abducted as a young boy to be trained and engineered into a Spartan. He doesn't even remember any siblings or relatives at all.