Teacher
Master, Doctor
noun
Previous life... So we're talking about someone who has a previous life, or maybe previous life experience? When you have previous life experience, you can teach others about it, making you qualified to be some kind of teacher.
せんせい
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
先生がアンナさんに手がみをかきました。
The teacher wrote a letter to Anna.
ダリン先生のつぎの休みはいつですか？
When is Dr. Darin's next day off?
先生と生徒の恋愛についてどう思いますか？
What do you think of love between a student and a teacher?